1.JS获取iframe下面的内容
document.getElementById('IFRAME1').contentDocument;
2.dialog 弹出层,定位:postion:'bottom',['right','bottom'],['left','bottom'].
3.IIS上部署WCF; 调用wcf或webapii一定要做安全认证。
cd d:
cd C:\Windows\Microsoft.NET\Framework\v4.0.30319
aspnet_regiis.exe -i
4.项目之间如何调用WCF,怎么调试？ 比如A项目,调用B项目的wcf服务。
a.先把B项目的wcf部署到IIS上,具体怎么部署？ 看上面的3
b.在A项目引用B项目部署在IIS上的地址。
c.在B项目中，把IIS的wcf附加到进程,打断点。
d.运行A项目,打断点调试。
写wcf执行的时候，可以作为启动想，选择特定的页为wcf文件，就可以直接输入参数，点击执行，返回执行结果。
5.
string a="1";
if (!a.IsNullOrEmpty())
{
//这种写法第一次看到，其实差不多。
}
if(!string.IsNullOrEmpty(a))
{
}
6.添加wcf可能报错，需要按如下图设置：
7.6.mysql 中可以用，Show Create Table '表名'，然后按F8，把创建脚步的语句拷贝出来。
8.用mysql客户端工具SQLyog,导入脚步，Tools -> Execute sql script.
9.redis 缓存，需要安装一个软件，一般情况下不需要做数据的持久化。
10.WCF 修改类具体实现的代码，引用WCF不需要更新，前提是方法名和参数名称没有改。
12.webAPI POSt处理SON数组：（后台是继承的属性，一定要用JSON.stringify，不然解析不了），而且前端只能穿一个参数，不然就会报500错误。get请求就没这个限制。
前端代码：
var mfItemStr = JSON.stringify({ mfItemStr: [{ "CreateId":1, "CreateName": "test1"},{ "CreateId":2, "CreateName": "test2"},{ "CreateId":3, "CreateName": "test3"}]});
$.ajax({
url: "/Test/Update",
type: "post",
dataType: "json",
contentType: "application/json",
data: mfItemStr,
success: function (data) {
console.log(data);
alert("Ok");
}
})
CSharp代码：
[HttpPost]
public HttpResponseMessage Update(JObject recordsSr)
{
var errMsg = new M_APIError();
try
{
if(recordsSr == null)
{
errMsg.ErrorCode = -1;
errMsg.Message = "recordsSr不能为空";
return Json.toJson(errMsg);
}
var str = recordsSr.ToObject<M_MFItem>();
if (str == null || str.mfItemStr == null || str.mfItemStr.Count <= 0)
{
errMsg.ErrorCode = -1;
errMsg.Message = "已选择的会员特性不能为空";
return Json.toJson(errMsg);
}
//已选择的会员特性
var records = str.mfItemStr;
int patientId = records.Select(t=>t.PatientID).First();
if (patientId <= 0)
{
errMsg.ErrorCode = -1;
errMsg.Message = "会员Id不能为空";
return Json.toJson(errMsg);
}
//获取当前会员的特性记录
var exists = new List<M_MemberFeaturesRecord>();
AspectF.Define.LogAPI(false).Do(() => exists = bll.GetMemberFeaturesRecordByPatientID(patientId));
if (exists == null && exists.Count <= 0)
{
errMsg.ErrorCode = -4;
errMsg.Message = "当前会员的特性记录为空";
}
else
{
//待新增记录(获取选中的记录不在当前会员的特性记录中的数据)
var adds = records.Where(c => !exists.Any(e => e.MFItemID == c.MFItemID)).ToList();
//给当前的特性记录加上特性名称，创建人和创建名称
exists.ForEach(t =>
{
var b = records.Where(a => a.MFItemID == t.MFItemID).FirstOrDefault();
if (b != null)
{
if (!string.IsNullOrWhiteSpace(b.MFItemName))
{
t.MFItemName = b.MFItemName;
}
if (b.CreateID > 0)
{
t.CreateID = b.CreateID;
}
if (!string.IsNullOrWhiteSpace(b.CreateName))
{
t.CreateName = b.CreateName;
}
}
});
//待删除记录
var deletes = exists.Where(c => !records.Any(e => e.MFItemID == c.MFItemID)).ToList();
//新增
var addResult = 0;
if (adds != null && adds.Count > 0)
{
AspectF.Define.LogAPI(false).Do(() => addResult = bll.BatchInsertMemberFeaturesRecord(adds));
if (addResult > 0)
{
AddmFRecordLog(patientId, adds, 1);
}
}
//删除
List<int> delList = new List<int>();
bool delResult = false;
if (deletes != null && deletes.Count > 0)
{
string recordIdStr = string.Join(",", deletes);
if (!string.IsNullOrWhiteSpace(recordIdStr))
{
AspectF.Define.LogAPI(false).Do(() => delResult = bll.BatchDeleteMemberFeaturesRecord(recordIdStr));
if (delResult)
{
AddmFRecordLog(patientId, deletes, 2);
}
}
}
if (addResult > 0 && delResult)
{
errMsg.ErrorCode = 0;
errMsg.Message = "成功";
errMsg.ReturnData = addResult;
}
else
{
errMsg.ErrorCode = -5;
errMsg.Message = "失败";
}
}
}
catch (Exception ex)
{
errMsg.ErrorCode = 500;
errMsg.Message = ex.Message;
}
return Json.toJson(errMsg);
}
13.ADO.NET 执行批量Sql server 的SQL,而mysql不支持,只能把批量的MySQL写在存储过程里面，然后调用。
sql server:
declare @result int;
set @result=-1092
if exists(select top 1 1 from [Order] a where A.OrderCurrentStatus=1 and A.Code=@Code)
begin
update [Order] set OrderCurrentStatus=2,OrderType=0 where Code=@Code;
--插入日志
INSERT INTO [OrderTrans]
([OrderId],[TransType],[OrderType],[OrderCode],
[IsResult],[Creater],[CreateDate],[Remark],[BusCode])
SELECT 0,3,0,@code,1,@Creater,GETDATE(),
'邮费订单审核',@code
set @result=@@error;
end
else
begin
set @result=1091
end
select @result;
14.h5增加类jquery
document.querySelector(".")
15.优化mysql的SQL,可以用explain,
EXPLAIN SELECT * FROM `accounts`
16.调试Wcf 和webAPI
C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\WcfTestClient.exe 调试调用WCF
调试webapi：
1).可以在chrome 添加插件Postman-REST-Client_v0.8.1
2).下载PC版 Postman-win64-5.0.0-Setup.exe https://download4os.com/postman-4-10-3-60258/
3).firefox 添加插件 httprequester
4).jmeter 参考地址: http://jingyan.baidu.com/article/14bd256e7e707cbb6d2612cf.html?qq-pf-to=pcqq.c2c
5).Fiddler 监控手机app程序和模拟post请求 参考如下:
https://www.cnblogs.com/-mrl/p/5081538.html
https://blog.csdn.net/qq_28766327/article/details/52457926
6). 接口的生成工具
17.MySQL数据库表字段生成对应的实体：
每个表生成实体类型，如果表字段很多的话，一个一个写很浪费时间，可以用正则(或动软代码生成器)来处理,正则步骤如下：
1.从MySQL中查询的信息中拿到createTable数据；SHOW CREATE TABLE sys_test 2.通过以下正则来替换 `(\S+)`\s+(\S+).*'(.*)', \t\t\/\/\/<summary>\n\t\t\/\/\/\t\3\n\t\t\/\/\/</summary>\n\t\t\[DataMember\]\n\t\tpublic \2 \1 \{ get; set;\}\n 通过正则之后，可以将table信息统一变成这种格式： /// <summary> /// 是否接受短信：0-否，1-是 /// </summary> [DataMember] public sbyte IsAcceptSMS { get; set; } 3.整理一些类型 ,int\(\d+\)-->int int\(\d+\) nvarchar\(\d+\)/text/char/varchar\(\d+\)--->string tinyint --->sbyte date/datetime --->DateTime time ---> TimeSpan bigint-->long smallint ->short int(11) unsigned -> uint double -> double bit -> bool decimal -> decimal blob -> byte[] float-> float
(\S+) sInfo\.\1 = info\.\1; info\.\1 = sInfo\.\1; \s+
Creator,
CreateTime,
TestLen,
OrderTest,
PlayAmount
先把,逗号替换掉，然后用(\S+)替换成sInfo\.\1 = info\.\1;
注意：可空的上面的正则处理不了。处理方法： 非空类型没有勾选(或为DEFAULT NULL)，C#定义需要可空类型。比如 tinyint 对 sbyte? 也可以通过Show full fields from TableA 看的Null列是否为YES，为YES就加？(字符串类型的不用加)
去掉换行：\s+ 替换为空格
18.uwp(Windows 10开发)
之前用到http://stackoverflow.com/questions/17049677/how-do-i-print-webview-content-in-a-windows-store-app 这个方法还是不行，因为我要打印曲线图。
a.打印页面，分页的方法：https://msdn.microsoft.com/zh-cn/library/windows/apps/xaml/hh465204
代码：https://code.msdn.microsoft.com/windowsapps/Print-Sample-c544cce6
b.打印webview嵌入html页面所有内容的方法（启动程序，打开谷歌浏览器，采用window.print打印）：
CSharp代码：
/// <summary>
/// 打印功能
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private async void ButtonPrint_Click(object sender, RoutedEventArgs e)
{
try
{
await SaveFileAsync(@"Report\jscript\data.js", "var jsonData = " + jsonData);
await LaunchFileAsync(@"Report\html\ReportDetail.html");
}
catch (Exception ex)
{
await new MessageDialog("打印失败").ShowAsync();
}
}
/// <summary>
/// 保存文件
/// </summary>
/// <param name="filePath">相对于localfilepath</param>
/// <param name="contents">内容</param>
/// <param name="options">选项m</param>
/// <returns></returns>
public static async Task SaveFileAsync(string filePath,string contents,CreationCollisionOption options= CreationCollisionOption.ReplaceExisting)
{
try
{
var localFolder = ApplicationData.Current.LocalFolder;
var file = await localFolder.CreateFileAsync(filePath, options);
await FileIO.AppendTextAsync(file, contents);
}
catch (Exception ex)
{
await FileLoger.WriteLog("savefile Error",ex,filePath);
}
}
/// <summary>
/// launch file
/// </summary>
/// <param name="filePath">相对于localfilepath</param>
/// <returns></returns>
public static async Task LaunchFileAsync(string filePath)
{
var localFolder = ApplicationData.Current.LocalFolder;
var file = await localFolder.CreateFileAsync(filePath, CreationCollisionOption.OpenIfExists);
await Windows.System.Launcher.LaunchFileAsync(file);
}
JS：方法
function ExecutePrint() {
setTimeout(function () {
if ($.browser.mozilla) {
document.getElementById("WebBrowserObj").execWB(7, 1);
}
else {
window.print();
}
}, 3000);
}
$(function () {
LoadData(jsonData);
ExecutePrint();
});
19. (1). mysql 可以利用GROUP_CONCAT把个值拼接在一起，默认以分号相隔。也可以指定其分隔符号。
GROUP_CONCAT(DISTINCT Guardian SEPARATOR ';') Guardian 以分号显示“a;b;c”
(2).mysql类型为time类型的时候，对应的C#定义为TimeSpan，赋值如下：
DateTime dt = DateTime.Parse("2016-6-29 19:20:30");
TimeSpan times = dt.TimeOfDay;//注意这里赋值
或
var tt = 490;
var ss = TimeSpan.FromMinutes(tt);
(3).C# 执行mysql脚本可以这样一起写：
INSERT INTO sys_log(`PatientID`,`MFItemID`,`MFItemName`,`CreateID`,`CreateName`,
`UpdateID`,`CreateTime`,`UpdateTime`,`DoctorID`,`DoctorName`,`DrID`,`DrName`,`OperationType`,`Remark`,`CARecordID`)
SELECT @NewPatientID,`MFItemID`,`MFItemName`,`CreateID`,`CreateName`,`UpdateID`,`CreateTime`,`UpdateTime`,`DoctorID`,`DoctorName`,`DrID`,`DrName`,`OperationType`,`Remark`,@RecordId
FROM sys_log WHERE `RecordLogID`=@RecordLogID;
(4).用CONCAT拼接字符串 LIKE CONCAT('%',@Title,'%')
(5).mysql获取自增的列的方法：区别可以参考：MYSQL LAST_INSERT_ID() 自增列详解 和 MySQL获取自增主键ID的四种方法
SELECT @@IDENTITY;
SELECT LAST_INSERT_ID();
(6).写方法，尽量使用参数，而不用直接传值，防止SQL注入，参数化安全性高些。 比如select * from A where id in(1,2,3)，可以select * from A where 1= 1 and (id=1 or id =2 or id=3) 。具体如下（注意红色标注的代码）：
public List<M_MTest> GetTetItemIds(int[] itemId)
{
if (itemId == null || itemId.Length < 1) return null;
const string sqlText = @"select * from Test where MFItemID=@ItemId";
var where = new StringBuilder(30, 30 * itemId.Length);
var param = new List<MySqlParameter>();
where.Append(" AND ");
if (itemId.Length == 1)
{
where.Append("MFItemID=@ItemId ");
param.Add(new MySqlParameter("@ItemId", itemId[0]));
}
else
{
where.Append("( ");
for (var i = 0; i < itemId.Length; i++)
{
where.Append("MFItemID=@ItemId");
where.Append(i);
if (i < itemId.Length - 1)
{
where.Append(" OR ");
}
param.Add(new MySqlParameter("@ItemId" + i, itemId[i]));
}
where.Append(" )");
}
var result = MySqlHelper.ExecuteDataTable(
MySqlHelper.ConnectionStringRemp,
CommandType.Text,
sqlText + @where,
param.ToArray()
);
return result.ConvertToList<M_MTest>();
}
int[] orgId;
const string sql =
"SELECT `MFTypeID`,`MFTypeName`,`MFTypeParentID`,`MFTypePath`,`MFTypeLevel`,`MFTypeOrder`,`Description`,`IsSystem`,`IsPushApp`,`IsDeleted`,`OrgID`,`CreateID`,`CreateTime`,`UpdateID`,`UpdateTime`,IFNULL((SELECT MFTypeID FROM sys_memberfeaturestype WHERE MFTypeParentID = s.MFTypeID limit 0,1),0) IsHasSub FROM sys_memberfeaturestype s where MFTypeParentID != -1 AND IsDeleted = 0";
var where = new StringBuilder();
var param = new List<MySqlParameter>();
if (orgId != null && orgId.Any())
{
if (orgId.Length == 1)
{
where.Append(" AND (OrgID = @OrgId OR OrgID = 0)");
param.Add(new MySqlParameter("@OrgId", orgId[0]));
}
else
{
where.Append(" AND ( OrgID = 0");
for (var i = 0; i < orgId.Length; i++)
{
where.Append(" OR");
where.Append(" OrgID = @OrgId");
where.Append(i);
param.Add(new MySqlParameter("@OrgId" + i, orgId[i]));
}
where.Append(" )");
}
}
对比：
if (orgIds != null && orgIds.Count > 0) { baseSql.AppendFormat(" and !d.IsDeleted and d.OrganizationID in ("); foreach (var orgId in orgIds) { baseSql.AppendFormat("{0},", orgId); } baseSql.Remove(baseSql.Length - 1, 1); baseSql.AppendFormat(")"); }
(7).mysql 批量新增：insert into Test(Id,name) value(1,"t"),(2,"test");
/// <summary>
///批量新增
/// </summary>
/// <param name="listTest">集合</param>
/// <returns></returns>
public int BatchInsertTEst(List<M_Test> listTest)
{
if (listTest == null || listTest.Count <= 0)
{
LogHelper.AddErrorLog("没有记录", "", "");
return -1;
}
var strSql =
new StringBuilder(
"INSERT INTO sys_Test(`PatientID`,`MFItemID`,`CreateID`,`CreateTime`) ");
var mysqlParam = new List<MySqlParameter>();
for (var i = 0; i < listTest.Count; i++)
{
var item = listTest[i];
if (i == 0)
{
strSql.AppendFormat(" VALUES(@PatientID{0},@MFItemID{0},@CreateID{0},@CreateTime{0})", i);
}
if (i > 0)
{
strSql.AppendFormat(",(@PatientID{0},@MFItemID{0},@CreateID{0},@CreateTime{0})", i);
}
mysqlParam.Add(new MySqlParameter(string.Format("@PatientID{0}", i), item.PatientID));
mysqlParam.Add(new MySqlParameter(string.Format("@MFItemID{0}", i), item.MFItemID));
mysqlParam.Add(new MySqlParameter(string.Format("@CreateID{0}", i), item.CreateID));
mysqlParam.Add(new MySqlParameter(string.Format("@CreateTime{0}", i), item.CreateTime));
}
try
{
var num = MySqlHelper.ExecuteNonQuery(MySqlHelper.connectionStringRemp, CommandType.Text,
strSql.ToString(), mysqlParam.ToArray());
return num;
}
catch (Exception ex)
{
LogHelper.AddErrorLog("批量新增失败", ex.ToString(), "");
return 0;
}
}
注意：这里没考虑大数据的问题，如一次性插入10万数据，就不能这样处理。 可以通过多线程的方式，每次给DB中添加1000条，另外的话还需要加上事务。可以参考下面的代码：
//设置CPU给当前应用程序分配的最小线程数
System.Threading.ThreadPool.SetMinThreads(100, 100);
var list = new List<Task>();
var count = 10000*10000;//1千万条
var num = 1000;//每次循环条数
for (int j = 0; j < count; j++)
{
//每次1000条数据
for (int i = 0; i < num; i++)
{
var result = Task.Run(() =>
{
//插入DB
});
list.Add(result);
}
//等待1000个线程跑完
Task.WaitAll(list.ToArray());
count = count - num;
}
(8).批量修改：
/// <summary>
/// 批量修改
/// </summary>
/// <param name="listmfRecordlog"></param>
/// <returns>是否成功</returns>
public bool BatchUpdateTest(List<M_Test> listTest)
{
var strSql = new StringBuilder();
var mysqlParam = new List<MySqlParameter>();
for (var i = 0; i < listTest.Count; i++)
{
var item = listTest[i];
strSql.AppendFormat(
"UPDATE sys_Test SET UpdateName = @UpdateName{0},UpdateTime=@UpdateTime{0},UpdateID=@UpdateID{0},OperationType=@OperationType{0} WHERE RecordLogID=@RecordLogID{0};",
i);
mysqlParam.Add(new MySqlParameter(string.Format("@UpdateName{0}", i), item.UpdateName));
mysqlParam.Add(new MySqlParameter(string.Format("@UpdateTime{0}", i), item.UpdateTime));
mysqlParam.Add(new MySqlParameter(string.Format("@UpdateID{0}", i), item.UpdateID));
mysqlParam.Add(new MySqlParameter(string.Format("@OperationType{0}", i), item.OperationType));
mysqlParam.Add(new MySqlParameter(string.Format("@CreateName{0}", i), item.CreateName));
mysqlParam.Add(new MySqlParameter(string.Format("@RecordLogID{0}", i), item.RecordLogID));
}
try
{
var num = MySqlHelper.ExecuteNonQuery(MySqlHelper.ConnectionStringRemp, CommandType.Text,
strSql.ToString(), mysqlParam.ToArray());
return num > 0;
}
catch (Exception ex)
{
LogHelper.AddErrorLog("批量修改失败", ex.ToString(), "");
return false;
}
}
(9).拼接SQL别用where 1=1，然后再拼接and，where 1=1 会先检索全表
const string sql = @"select * from table "; var where = new StringBuilder(); if (!string.IsNullOrWhiteSpace(xx)) { where.AppendFormat(" where id = {0}",xx); } if (!string.IsNullOrWhiteSpace(yy)) { where.Append(where.Length > 1 ? " and" : "where"); where.AppendFormat(" name = {0}",yy); } var sqlstr = sql + where;
20.SQL里面如果排序不了，可以多利用linq 或lamber表达式排序。
21.前端JS通过数组，传一个对象给ASP.net MVC 的后台方法。后台定义一个实体类和前端的名称一致，Mvc会自动转化。
JS代码：
function btnSave() {
var btnSave = document.getElementById("btnSave");
//将表单提交按钮设置为不可用，这样就可以避免用户再次点击提交按钮
btnSave.disabled = true;
if ($("#Remark").val() == "") {
alert("备注不能为空");
btnSave.disabled = false;
return false;
}
var data = {};
data["data.CallStatus"] = $("#CallStatus").val();
data["data.ITime"] = $("#ITime").val();
data["data.Remark"] = $("#Remark").val();
data["data.IResult"] = $("#IResult").val();
$.ajax({
type: 'post',
url: "/TestWeb/TestActivity/TestDetail",
datatype: 'json',//返回json格式的数据
data: data,
error: function (XHR) {
alert('网络异常，请稍候再试');
btnSave.disabled = false;
},
success: function (data) {
if (data.Success) {
alert("添加成功");
} else {
alert("添加失败");
}
}
});
}
C#代码：
[HttpPost]
public JsonResult TestDetail(M_TestDetail data)//这里data要和前端的data["data.CallStatus"] 中括号里面的data名称一样，对应的字段名该实体类字段名称一样。MVC会自动转化
{
var msg = new ResultMsgInfo();
msg.Msg = "保存成功";
msg.Success = true;
return Json(msg, JsonRequestBehavior.AllowGet);
}
M_TestDetail实体类：
[DataContract]
public class M_TestDetail
{
///<summary>
/// 邀约电话接通情况：0 接听成功 1 无人接听 2 拒接 3 信息错误 4 空号 5 号码过期 6 未接通 7 通话中
///</summary>
[DataMember]
public sbyte? CallStatus { get; set; }
///<summary>
/// 同意到场时间
///</summary>
[DataMember]
public string ITime { get; set; }
///<summary>
/// 备注
///</summary>
[DataMember]
public string Remark { get; set; }
///<summary>
/// 邀约结果：0 无 1 来 2 不来 3 待定 4 重新邀约
///</summary>
[DataMember]
public sbyte? IResult { get; set; }
}
22.Json转换实体,使用 Deserialize<M_TestDetail>(jsonData); 需要引入Newtonsoft.Json.dll
public T Deserialize<T>(string json)
{
T obj = Activator.CreateInstance<T>();
var result = JsonConvert.DeserializeObject<T>(json);
return result;
}
23.ASP.Net MVC
(1).页面判断，里面的文本需要加<text></text>,如下：
<input type="checkbox" @if (dateAm != null && dateAm.Count > 0) {<text> checked="checked"</text> }/>
(2). Html.RenderAction的使用
cshtml 代码：
@{Html.RenderAction("JudgementStatus", new { num = item.CallStatus, statusName = "CallStatus" });}
控制器的C#代码：
/// <summary>
/// 获取状态描述
/// </summary>
/// <param name="num"></param>
/// <param name="statusName"></param>
/// <returns></returns>
public string JudgementStatus(sbyte? num, string statusName)
{
var str = string.Empty;
switch (statusName)
{
case "CallStatus":
if (num.HasValue)
{
switch (num.Value)
{
//0 接听成功 1 无人接听 2 信息错误 3 拒接 4 空号 5 号码过期 6 未接通 7 通话中
case 0: str = "接听成功"; break;
case 1: str = "无人接听"; break;
case 2: str = "拒接"; break;
case 3: str = "信息错误"; break;
case 4: str = "空号"; break;
case 5: str = "号码过期"; break;
case 6: str = "未接通"; break;
case 7: str = "通话中"; break;
default: str = ""; break;
}
}
else
{
str = ""; break;
}
break;
case "IsSign":
if (num.HasValue)
{
switch (num.Value)
{
case 0: str = "未到场"; break;
case 1: str = "已到场"; break;
default: str = ""; break;
}
}
else
{
str = "未到场"; break;
}
break;
}
return str;
}
24.时间处理的时候，不要用js的toLocaleDateString(); 因为兼容性不好,还要考虑到服务器后台解析的兼容性，在Microsoft Edge序列化数组的时候，传到后台mvc，反序列化DataTime直接报错，而且把datatime改成string,然后通过Convert.ToDateTime("2016-8-29")转化不了，原因是编码的问题，当我把2016-8-29拷贝到记事本里面保存，然后重新打开直接出现？。可以改成拼接的写法：
var start = new Date($("#StartDate").val());
new Date(start).toLocaleDateString();
上面的写法改成如下：
var month = new Date(start).getMonth() + 1;
var datatostring = new Date(start).getFullYear() + "-" + month + "-" + new Date(start).getDate();
var _oneDay = new Date(start.setDate(start.getDate() + 1));
var month = new Date(_oneDay).getMonth() + 1;
var datatostring = new Date(start).getFullYear() + "-" + month + "-" + new Date(start).getDate();
IE10出现兼容性可以用下面的方法处理：
.replace("年", "/").replace("月", "/").replace("日", "").replace(/\?/g, "");
.replace("-", "/")
replace("/", "-")
25.JS： var re = /^[0-9]*[1-9][0-9]*$/; //正整数
.replace(/\?/g, "");去掉?
26.展示mysql变量的函数 SHOW VARIABLES LIKE '%skip%';
27.C#访问本地mysql出现“ HOST 'test' IS NOT allowed TO connect TO this MySQL server” ?
解决方法：(1).如下图 (2).找到安排目录的C:\Program Files\MySQL\MySQL Server 5.5\my.ini，打开my.ini，加上skip_name_resolve=1，重启mysql服务。
28.jQuery 可以通过commitForm提交表单，mvc接受值，建议使用FormCollection取值，不要使用request取值
<form id="f1" method="POST">
<h2>AddAddress</h2>
<input type="text" name="Address"/>
<input type="text" name="Name"/>
<input id="Submit1" type="submit" value="submit"/>
</form>
<script type="text/javascript">
$(function() {
$("#f1").commitForm({
url: '/home/test',
callBack:function(data) {
alert(data);
}
});
});
</script>
29.大数据并发出来：a.负载均衡（建多个站点,nginx(参考https://lufficc.com/blog/configure-nginx-as-a-web-server) ） b.使用缓存
30.数据的同步可以通过Quartz.net 写job处理，需要按时间来升序，需要考虑到相同时间的数据。
31.mysql 调用存储过程
SET @iDrID=2; SET @vPatientName=''; SET @vSchemeTitle=''; SET @dSCreateTime=''; SET @dECreateTime=''; SET @iCheckSuggestFlag=-1; SET @iCurrentPageIndex=0; SET @iPageSize=10; CALL proc_Scheme_QueryList(@iDrID,@vPatientName,@vSchemeTitle,@dSCreateTime,@dECreateTime,@iCheckSuggestFlag,@iCurrentPageIndex,@iPageSize,@iRowCount); SELECT @iRowCount;
32.C#发送http 请求：1.HttpWebRequest 2.HttpClient（webapi）
33.直接返回某列的list集合
public List<int> GetAlltestIds() { const string sql = " select testId from sys_test "; var ds = MySqlHelper.ExecuteDataSet(ConnectionStringConfig.DataCenter, CommandType.Text, sql, new MySqlParameter[] { }); var list = ds.Tables[0].Rows.Cast<object>().Select((r, i) => Convert.ToInt32(ds.Tables[0].Rows[i][0])).ToList(); return list; }
34.通过ASP.MVC自带的传参数到后台进行新增
public ActionResult Register()
{
var vmodel = new M_UserTest();
return View(vmodel);
}
public ActionResult RegisterTest(M_UserTest data)
{
var result = bll.Add(data);
return View();
}
@using Model @model M_UserTest @{ ViewBag.Title = "Register"; } <h2>Register</h2> <div class="row"> <div class="col-md-8"> <section id="loginForm"> @using (Html.BeginForm("RegisterTest", "Home", new { ReturnUrl = ViewBag.ReturnUrl }, FormMethod.Post, new { @class = "form-horizontal", role = "form" })) { <div class="form-group"> <label class="col-md-2 control-label">用户名</label> <div class="col-md-10"> @Html.TextBoxFor(m => m.username, new { @class = "form-control" }) </div> </div> <div class="form-group"> <label class="col-md-2 control-label">账号</label> <div class="col-md-10"> @Html.TextBoxFor(m => m.userAccount, new { @class = "form-control" }) </div> </div> <div class="form-group"> <label class="col-md-2 control-label">密码</label> <div class="col-md-10"> @Html.PasswordFor(m => m.userPwd, new { @class = "form-control" }) </div> </div> <div class="form-group"> <div class="col-md-offset-2 col-md-10"> <input type="submit" value="注册" class="btn btn-default" /> </div> </div> } </section> </div> </div>
35.MySQL修改字段默认值和修改字段长度
use `test_ch`; /*修改字段默认值*/ alter table hm_test modify AuditStatus tinyint not null default 1 comment '审核状态 0.未审核，1.已审核'; /*修改字段长度*/ alter table hm_test modify column Summary varchar(2000);
36.C#把字符串数组转化成List
/// <summary> /// 把字符串数组转化成List /// </summary> /// <param name="target">字符串</param> /// <returns></returns> public static List<int> AsList(this string[] target) { var arr = new List<int>(); if (target == null || target.Length == 0) return arr; Array.ForEach(target, id => { int tmpId; if (int.TryParse(id, out tmpId)) { arr.Add(tmpId); } }); return arr; }
string scGoodIds = "1,2,,3,4,5,6,7"; var ids = scGoodIds.Split(new[] { "," }, StringSplitOptions.RemoveEmptyEntries).AsList();
37.用EF写出一条分页语句，页码数是1，页大学为20. 可参考LINQ系列：LINQ to SQL Take/Skip
pageIndex PageSize
var reulst = (from u in uList
orderby u.toolingNo
select u).Skip(pageSize *(pageIndex -1)).Take(pageSize);
OrderBy 是排序（后面是条件）然后要查询所有的，在所有的数据中在查询你要分页的数据，skip是在分页在前有多少条数据，也就是在当前页数据之前的数据总和，(跳过序列中指定数量的元素，然后返回剩余的元素。)pageSize*(pageIndex-1),Take 是返回多少条数据，也就是pageSize!
38.ling分组，处理
var IaidList = times.GroupBy(p => p.IAId).ToDictionary(p => p.Key, r => r.Select(o => o)).OrderBy(p => p.Key).ToList();
2)linq 分组去除重复的某项
var result = testItem.GroupBy(t => t.TestItemCode).Select(t => t.OrderByDescending(p => p.CreatedTime).OrderByDescending(p => p.TestItemID).FirstOrDefault());
3).分组汇总
q = q.GroupBy(t => t.CreateDate).Select(g => new TestData { CreateDate = g.Key, Num = g.Sum(p => p.Num), });
39.Quartz.net 安装服务和卸载服务
安装服务：
@Test.exe install
@pause
@exit
保存记事本里面，后缀名为.bat
卸载服务：
@Test.exe uninstall
@net start Test
@pause
@exit
40.C# 对象转jSON 时 过滤 NULL 的属性 参考：https://q.cnblogs.com/q/72031/ http://www.newtonsoft.com/json/help/html/ReducingSerializedJSONSize.htm 需要引用Newtonsoft.Json.dll
public class Person { public int Id { get; set; } public string Name { get; set; } }
static void Main(string[] args) { var list = new List<Person>(); for (int i = 1; i < 5; i++) { list.Add(new Person() { Id = i, Name = "test" + i }); } list.Add(new Person() { Id = 5, Name = null, }); string ignored = JsonConvert.SerializeObject(list, Formatting.Indented, new JsonSerializerSettings { DefaultValueHandling = DefaultValueHandling.Ignore });
//[{"Id":1,"Name":"test1"},{"Id":2,"Name":"test2"},{"Id":3,"Name":"test3"},{"Id":4,"Name":"test4"},{"Id":5}] var test = JsonConvert.DeserializeObject<List<Person>>(ignored); Console.ReadLine(); }
41.怎么监控EF生成的sql
1).EntityFramework Profiler， 下载地址：https://hibernatingrhinos.com/products/EFProf
2). 如果是SQL server 可以用SQL Server Profiler, 具体可以参考：http://www.cnblogs.com/allenhua/p/3533975.html
42.去掉webapi的token验证。在compilation 家debug="true" 。 <compilation debug="true" targetFramework="4.5" />
43. IIS初始化（预加载），解决第一次访问慢，程序池被回收问题
44.计算时间
Stopwatch stopwatch = new Stopwatch(); //第一次计时 stopwatch.Start(); Console.WriteLine("Stopwatch is running:{0}",stopwatch.IsRunning);//判断当前Stopwatch的状态 System.Threading.Thread.Sleep(1000);//耗时操作 stopwatch.Stop(); Console.WriteLine("Using Elapsed output runTime:{0}", stopwatch.Elapsed.ToString());//这里使用时间差来输出 Console.WriteLine("Using ElapsedMilliseconds output runTime:{0}", stopwatch.ElapsedMilliseconds);//这里面使用毫秒来输出
45.调用数据库或服务，一定要释放。 可以通过查看oracle的连接数来看是否是否资源 select count(*) from v$session;
1).单个写
using (testService as IDisposable) { persont = testService.GetTest(name); }
2).在基类写，实现IDisposable。
private bool disposed = false; protected virtual void Dispose(bool disposing) { if (!this.disposed) { if (disposing && _context != null) { _context.Dispose(); } } this.disposed = true; } public void Dispose() { Dispose(true); GC.SuppressFinalize(this); }
46. EF 修改数据出现：Attaching an entity of type 'HR_TEST' failed because another entity of the same type already has the same primary key value. This can happen when using the 'Attach' method or setting the state of an entity to 'Unchanged' or 'Modified' if any entities in the graph have conflicting key values. This may be because some entities are new and have not yet received database-generated key values. In this case use the 'Add' method or the 'Added' entity state to track the graph and then set the state of non-new entities to 'Unchanged' or 'Modified' as appropriate.
原先代码：
public bool Update(TEntity entity) { _context.Entry<TEntity>(entity).State = EntityState.Modified; return _context.SaveChanges() > 0; }
改成：
public bool Update(TEntity entity, Func<TEntity, int> getKey) { // Retreive the Id through reflection var entry = _context.Entry<TEntity>(entity); if (entry.State == EntityState.Detached) { var set = _context.Set<TEntity>(); TEntity attachedEntity = set.Find(getKey(entity)); // access the key if (attachedEntity != null) { var attachedEntry = _context.Entry(attachedEntity); attachedEntry.CurrentValues.SetValues(entity);
AttachedEntry.State = EntityState.Modified; } else {
set.Attach(entity); entry.State = EntityState.Modified; // attach the entity } } return _context.SaveChanges() > 0; }
47.可以用action定义实体转化
//定义动态映射函数 Action<Patient> action = (Patient member) => { person.Name = member.Name; person.Gender = member.Sex; person.BirthDate = !string.IsNullOrWhiteSpace(member.Birthday) ? member.Birthday.Replace("-", "") : person.BirthDate;//系统中的生日全部是yyyyMMdd格式 person.Nationality = member.Ethnic; person.CensusAddressName = member.Domicile; person.Country = country; person.IDNumber = idcard; person.IDType = idType; };
48.C#生成随机流水号:
public static string GenerateOrderId() { string text = string.Empty; System.Random random = new System.Random(); for (int i = 0; i < 7; i++) { int num = random.Next(); text += ((char)(48 + (ushort)(num % 10))).ToString(); } return System.DateTime.Now.ToString("yyyyMMdd") + text; }
49.redis加入到Windows 服务
安装命令:
redis-server.exe --service-install redis.windows.conf --loglevel verbose
卸载命令：
redis-server --service-uninstall
50.异步调用
1).
Task.Run(() =>
{
Test();
});
2).
Action act = () => Test(); act.BeginInvoke(t => act.EndInvoke(t), null);
51.C# 调用webApi
1).webpai Post
[Route("CheckUp"), HttpPost] public IHttpActionResult CheckUp(CheckUp request) { return Ok(new { Status = 0, Msg = "" }); }
调用代码
1).
/// <summary> /// 需要引用 System.Net.dll,System.IO.dll /// </summary> /// <param name="url">url</param> /// <param name="headers">头文信息</param> /// <param name="format">格式</param> /// <param name="formData">传入数据格式</param> /// <returns></returns> public static string Post(string url, Dictionary<string, string> headers, string format, string formData) { byte[] postData = Encoding.UTF8.GetBytes(formData); HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest; request.Method = "POST"; request.AllowAutoRedirect = false; request.ContentType = format+";charset=utf-8"; request.KeepAlive = false; request.ProtocolVersion = HttpVersion.Version10; request.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.6)"; if (headers != null) { foreach (KeyValuePair<string, string> item in headers) { request.Headers.Add(item.Key, item.Value); } } request.ContentLength = postData.Length; // 开始请求 using (Stream postStream = request.GetRequestStream()) { postStream.Write(postData, 0, postData.Length); } HttpWebResponse response = request.GetResponse() as HttpWebResponse; Stream s = response.GetResponseStream(); StreamReader reader = new StreamReader(s, Encoding.GetEncoding("UTF-8")); string result = reader.ReadToEnd(); reader.Close(); s.Close(); if (response != null) response.Close(); if (request != null) request.Abort(); return result; }
Post(url, new Dictionary<string, string>(), "application/json", JsonConvert.SerializeObject(checckup));
2).
//定义Request 并设置request的路径 WebRequest request = WebRequest.Create(url); request.Method = "post"; //设置参数的编码格式，解决中文乱码 byte[] byteArray = Encoding.UTF8.GetBytes(data); //设置Request的MINE类型及内容长度 request.ContentType = "application/json"; request.ContentLength = byteArray.Length; //打开request字符流 Stream dataStream = request.GetRequestStream(); dataStream.Write(byteArray, 0, byteArray.Length); dataStream.Close(); //定义response为前面的request响应 WebResponse response = request.GetResponse(); //获取相应的状态代码 var str = ((HttpWebResponse)response).StatusCode; //定义response字符流 dataStream = response.GetResponseStream(); StreamReader reader = new StreamReader(dataStream); string responseFormServer = reader.ReadToEnd();//读取所有
3).
url = url + "/api/test/login"; var list = request.ToDictionary(); var data = new NameValueCollection(); foreach (var item in list) { if (item.Value != null) { data.Add(item.Key, item.Value.ToString()); } } WebClient wc = new WebClient(); byte[] result = wc.UploadValues(url, "POST", data); var response = System.Text.Encoding.UTF8.GetString(result);
4).http get 和post 调用webapi 方法
#region post信息 /* string content = Post('url', new Dictionary<string, string>(), "application/json", Utils.ModelToJson(new testModel { testcard = '', testtype = '' })) */ /// <summary> /// post信息 /// </summary> /// <param name="url"></param> /// <param name="headers"></param> /// <param name="format"></param> /// <param name="formData"></param> /// <returns></returns> public static string Post(string url, Dictionary<string, string> headers, string format, string formData) { byte[] postData = Encoding.UTF8.GetBytes(formData); HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest; request.Method = "POST"; request.AllowAutoRedirect = false; request.ContentType = format+";charset=utf-8"; request.KeepAlive = false; request.ProtocolVersion = HttpVersion.Version10; request.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.6)"; if (headers != null) { foreach (KeyValuePair<string, string> item in headers) { request.Headers.Add(item.Key, item.Value); } } request.ContentLength = postData.Length; // 开始请求 using (Stream postStream = request.GetRequestStream()) { postStream.Write(postData, 0, postData.Length); } HttpWebResponse response = request.GetResponse() as HttpWebResponse; Stream s = response.GetResponseStream(); StreamReader reader = new StreamReader(s, Encoding.GetEncoding("UTF-8")); string result = reader.ReadToEnd(); reader.Close(); s.Close(); if (response != null) response.Close(); if (request != null) request.Abort(); return result; } #endregion #region 获取get消息 /// <summary> /// 获取get消息 /// </summary> /// <param name="format">xml,json选择返回</param> /// <param name="url"></param> /// <param name="headers"></param> /// <returns> HttpHelper.Get("json", url + "/api/patient/getpatientbyphone?phone=" + phoneNo, null);</returns> public static string Get(string format, string url, Dictionary<string, string> headers) { HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest; request.Method = "GET"; request.AllowAutoRedirect = false; request.ContentType = "text/" + format + ";charset=utf-8"; request.KeepAlive = false; request.ProtocolVersion = HttpVersion.Version10; request.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.6)"; if (headers != null) { foreach (KeyValuePair<string, string> item in headers) { request.Headers.Add(item.Key, item.Value); } } HttpWebResponse response = request.GetResponse() as HttpWebResponse; Stream s = response.GetResponseStream(); StreamReader reader = new StreamReader(s, Encoding.GetEncoding("UTF-8")); string result = reader.ReadToEnd(); reader.Close(); if (s != null) s.Close(); response.Close(); request.Abort(); return result; } #endregion
5).webapi
[Route("CheckUp"), HttpPost] public IHttpActionResult CheckUp([FromBody] string baseRequest) { }
调用代码
//设置HttpClientHandler的AutomaticDecompression var handler = new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.GZip }; //创建HttpClient（注意传入HttpClientHandler） using (var http = new HttpClient(handler)) { //使用FormUrlEncodedContent做HttpContent var content = new FormUrlEncodedContent(new Dictionary<string, string>() { {"",data}//键名必须为空,data为json字符串 }); //await异步等待回应 var response = await http.PostAsync(url, content); //确保HTTP成功状态值 response.EnsureSuccessStatusCode(); //await异步读取最后的JSON（注意此时gzip已经被自动解压缩了，因为上面的AutomaticDecompression = DecompressionMethods.GZip） await response.Content.ReadAsStringAsync(); }
52. C# async和await string 转为Task<string>
public static async Task<string> Test(string[] inputs) { StringBuilder sBuilder = new StringBuilder(); for (int i = 0; i < 10; i++) { sBuilder.Append(i.ToString("x2")); } return await Task.FromResult(sBuilder.ToString()); }
53. 实体转化不用重新写方法，可以用委托（Action<T>）来实现，demo如下：
private void Test(PersonInfoModels data) { Action<PersonInfoModels> action = (PersonInfoModels m) => { person.Name = m.Name; } if (data != null) {
//调用 action(data); } }
54.Linq To Sql中实现Left Join与Inner Join使用Linq语法与lambda表达式
当前有两个表，sgroup与sgroupuser，两者通过gKey关联，而sgroup表记录的是组，而sgroupuser记录是组中的用户，因此在sgroupuser中不一定有数据。需要使用Left Join获取数据：
Linq语法如下:
var sg = (from g in dc.sgroup
join gu in dc.sgroupuser on g.gKey equals gu.gKey into l
from lgu in l.DefaultIfEmpty()
select new { g, lgu }).ToList();
Lambda表达式如下：
var sg = dc.sgroup.GroupJoin(dc.sgroupuser, g => g.gKey, gu => gu.gKey, (g, gu) => new { g, gu }).Select(o=>o).ToList() ;
注意:
Linq 与Lambda表达式取出的结果有所不同.Linq取出的结果的记录数与Sql中的Left Join的结果相同,而Lambda表达式取出的记录数是sgroup表中的记录数,sgroupuser对应的记录是以对象集合存在于结果中
附:
下面是Inner Join:
Linq语法如下:
var sg = (from g in dc.sgroup
join gu in dc.sgroupuser on g.gKey equals gu.gKey
select new { g, gu }).ToList();
Lambda表达式如下：
var sg = dc.sgroup.Join(dc.sgroupuser, g => g.gKey, gu => gu.gKey, (g, gu) => new { g, gu }).Select(o=>o).ToList() ;
注意:
上面最后都用到了ToList()方法 , 用ToList()是为了一次性将数据取到本地
http://www.cnblogs.com/xinjian/archive/2010/11/17/1879959.html
55.
1).linq 实现left join,并在on 后面添加and
var list = from a in bloodlist join b in sugarlist on new { a.OrganizationID,a.MonitorDate } equals new { b.OrganizationID, b.MonitorDate } into sugarTemp from newb in sugarTemp.DefaultIfEmpty() select new DetectData { OrganizationID = a.OrganizationID, MonitorDate = a.MonitorDate, DayBloodPressureNum = a.DayBloodPressureNum, DaySugarPressureNum = newb != null ? newb.DaySugarPressureNum : 0 };
2).let
result = (from b in bloodlist join s in sugarlist on new { b.OrganizationID, b.MonitorDate } equals new { s.OrganizationID, s.MonitorDate } select new BI_IndexDetectData { MonitorDate = b.MonitorDate, OrganizationID = b.OrganizationID, DayBloodPressureNum = b.DayBloodPressureNum, DaySugarPressureNum = s.DaySugarPressureNum, }).ToList(); var result1 = (from b in bloodlist join s in sugarlist on new { b.OrganizationID, b.MonitorDate } equals new { s.OrganizationID, s.MonitorDate } let daySugarPressureNum = s.DaySugarPressureNum where s.DaySugarPressureNum > 0 select new BI_IndexDetectData { MonitorDate = b.MonitorDate, OrganizationID = b.OrganizationID, DayBloodPressureNum = b.DayBloodPressureNum, DaySugarPressureNum = daySugarPressureNum, }).ToList();
56.C#递归根据日期分页获取所有满足条件的体检信息
调用 var dataresult = GetPageOfAllCheckUpRegInfo(pageIndex, pageSize, BeginCheckDate.Value, endCheckUpDate.Value,isVip);
#region 根据总检日期和页码获取所有满足条件的体检登记信息 /// <summary> /// 根据总检日期和页码获取所有满足条件的体检登记信息 /// </summary> /// <param name="pageIndex">当前页码</param> /// <param name="pageSize">页大小</param> /// <param name="bcheckUpDate">总检开始日期</param> /// <param name="echeckUpDate">总检结束日期</param> /// <returns></returns> private List<CheckUpRegInfo> GetPageOfAllCheckUpRegInfo(int pageIndex, int pageSize, DateTime bcheckUpDate, DateTime echeckUpDate, string isVip) { var result = new List<CheckUpRegInfo>(); // 递归获取所有满足条件的体检登记信息 GetAllCheckUpRegInfo(pageIndex, pageSize, bcheckUpDate, echeckUpDate,isVip,result); return result; } #endregion #region 递归获取体检登记信息 /// <summary> /// 递归调用 /// </summary> /// <param name="pageIndex">当前页码</param> /// <param name="pageSize">页大小</param> /// <param name="bcheckUpDate">总检开始日期</param> /// <param name="echeckUpDate">总检结束日期</param> /// <param name="isVip">是否vip</param> /// <param name="result">返回结果</param> private void GetAllCheckUpRegInfo(int pageIndex, int pageSize, DateTime bcheckUpDate, DateTime echeckUpDate,string isVip,List<CheckUpRegInfo> result) { try { var req = new CheckUpDataInput(); req.BeginCheckDate = bcheckUpDate; req.EndCheckDate = echeckUpDate; req.PageSize = pageSize; req.PageIndex = pageIndex; req.SortType = false; req.OrderBy = "JCRQ";//总检日期 req.IsVip = isVip; CheckService = new AutoCheckService(req); var dataResult = CheckService.GetPageOfCheckUpRegInfo(); //释放资源 using (CheckService as IDisposable) { } if (dataResult != null && dataResult.ResultCode == 100) { var list = dataResult.Result.ToList(); if (list != null && list.Count > 0) { var PageCount = dataResult.PageCount; //本页执行完成，继续执行下一页 if (pageIndex <= PageCount) { pageIndex++; result.AddRange(list); GetAllCheckUpRegInfo(pageIndex, pageSize, bcheckUpDate, echeckUpDate, isVip, result); } } } } catch (Exception ex) { WriteLog("GetAllCheckUpRegInfo递归获取体检登记信息:" + ex.Message); } } #endregion
57.将字符串转为int，否则返回默认值
/// <summary> /// 将字符串转为int，否则返回默认值 /// </summary> /// <param name="values"></param> /// <returns></returns> public static int[] ToIntArray(this string[] values) { int len = values.Length; var indexIds = new int[len]; for (int i = 0; i < len; i++) { indexIds[i] = values[i].ToInt(0); } return indexIds; }
58.EF 中必须 AsEnumerable() 之后才能group by
1).IQueryable 有诸多限制, 只支持数据库查询语法, 无法支持 Linq to object 的操作.
2).加了 AsEnumerable() 后运行正常, 因为 IEnumerable 支持 Linq to object 的操作.
简述Linq中.ToList(), .AsEnumerable(), AsQueryable()的区别和用法
LINQ语句中的.AsEnumerable() 和 .AsQueryable()的区别
/// <summary> /// 分组查询 /// </summary> /// <typeparam name="S"></typeparam> /// <typeparam name="T"></typeparam> /// <param name="request"></param> /// <param name="whereAndOrderBy"></param> /// <returns></returns> public virtual BaseResponse<IList<T>> GroupQuery<S, T>(BaseRequest request, Func<IEnumerable<S>, IEnumerable<S>> whereAndOrderBy) where S : class { BaseResponse<IList<T>> response = new BaseResponse<IList<T>>(); //Mapper.CreateMap<S, T>(); var q = from m in unitOfWork.GetRepository<S>().dbSet.AsEnumerable() select m; if (whereAndOrderBy != null) { q = whereAndOrderBy(q); } //创建一个参数c ParameterExpression param = Expression.Parameter(typeof(S), "c"); //c.IsDeleted=="false" Expression left = Expression.Property(param, typeof(S).GetProperty("IsDeleted")); Expression right = Expression.Constant(false); Expression filter = Expression.Equal(left, right); Expression pred = Expression.Lambda(filter, param); //Where(c=>c.IsDeleted==false) //Expression expr = Expression.Call(typeof(Queryable), "Where", // new Type[] { typeof(S) }, // Expression.Constant(q), pred); //生成动态查询 //q = q.Provider.CreateQuery<S>(expr); q = q.AsQueryable().Where((Expression<Func<S, bool>>)pred); response.RecordsCount = q.Count(); List<S> list = null; if (request != null && request.PageSize > 0) { list = q.Skip((request.CurrentPage - 1) * request.PageSize).Take(request.PageSize).ToList(); response.PagesCount = GetPagesCount(request.PageSize, response.RecordsCount); } else { list = q.ToList(); } //response.Data = Mapper.Map<IList<T>>(list); response.Data = Mapper.DynamicMap<IList<T>>(list); return response; }
59.EF 传实体，不能更新，需要先根据某个条件查询实体，然后再把传过来的值赋上，就可以更新实体。
60.实现一个条记录里面两个值要成对出现
思路:分别查出两个结果集，进行union(MySQL 里面用union),然后在根据主键ID分组，having count(Id)= 2，根据时间降序。
方法一 Linq 实现
var idlist = (from p in result group p by p.ExaminationID into h select new { key = h.Key, count = h.Count(), examDate = h.FirstOrDefault().ExaminationTime } into c where c.count == 2 orderby c.examDate descending select c).Select(t => t.key).Take(7).ToList();
对应mysql 语句表示
SELECT * result GROUP BY ExaminationID HAVING COUNT(ExaminationID ) = 2 ORDER BY ExaminationTime DESC LIMIT 7
方法二
var rest = (from height in resultHeight join weight in resultWeight on height.ExaminationID equals weight.ExaminationID select new { ExaminationTime = height.ExaminationTime, CheckValueHeight = height.CheckValue, CheckValueWeight = weight.CheckValue, }).OrderByDescending(t => t.ExaminationTime).Take(7).ToList()
61.C# 正则 匹配字符中整个url
string str="网址为http://test.com/?key=123123 ,祝您生活愉快"; Regex re = new Regex("(https?|ftp|file)://[-A-Za-z0-9+&@#/%?=~_|!:,.;]+[-A-Za-z0-9+&@#/%=~_|]"); MatchCollection mc = re.Matches(str); var url = ""; foreach (Match m in mc) { url = m.ToString(); }
62.监控网站，可以监控EF生成的sql dynatrace
63.asp.net webapi 集成swagger 自动生成webapi文档
64.C#上传图片重新命名图片，防止重名。
65.筛选结果成对出现
1).linq
var list = (from item in testDataList where new List<string>() { "101", "102" }.Contains(item.TestCode) group item by item.testID into temp select new { key = temp.Key, count = temp.Count() } into c where c.count == 2 select c).ToList();
2).sql
SELECT COUNT(*),testCode,Value,Exid FROM CM_test WHERE testCode IN('101','102') GROUP BY Exid HAVING COUNT(*) = 2
66.C#int类型相乘
Math.Round((decimal)singeTotal / (decimal)totalResult * (decimal)100.0, 2)
67. /分割并去除空值
//分割并去除空值 "1,2,13,4,5,,".Split(new string[] { "," }, StringSplitOptions.RemoveEmptyEntries);
68.Visual Studio 2017 单元测试运行不了的解决办法
将测试项目的引用 Microsoft.VisualStudio.TestPlatform.TestFramework、Microsoft.VisualStudio.TestPlatform.TestFramework.Extensions 删掉
添加 Microsoft.VisualStudio.QualityTools.UnitTestFramework(通过Nuget添加) 既可
69.添加Debug测试
#if !DEBUG //不是debug模式 var account = CurrentAccount; if (account!=null) { return account.ID; } return -1; #else //是debug模式 return 6378; #endif
70.使用redis 实现Session["checkCode"] 的功能,参考 不用session的验证码。登录实现图片验证码功能为例
ValidateCode.cs:
/// <summary> /// 验证码 /// </summary> public static class ValidateCode { #region 生成验证码 /// <summary> /// 生成验证码 /// </summary> /// <param name="length">指定验证码的长度</param> /// <returns>验证码</returns> public static string[] CreateValidateNumber(int length) { string Vchar = "1,2,3,4,5,6,7,8,9,a,b,c,d,e,f,g,h,i,j,k,l,m,n,p" + ",q,r,s,t,u,v,w,x,y,z,A,B,C,D,E,F,G,H,I,J,K,L,M,N,P,Q" + ",R,S,T,U,V,W,X,Y,Z"; string[] VcArray = Vchar.Split(new Char[] { ',' });//拆分成数组 string[] num = new string[length]; int temp = -1;//记录上次随机数值，尽量避避免生产几个一样的随机数 Random rand = new Random(); //采用一个简单的算法以保证生成随机数的不同 for (int i = 1; i < length + 1; i++) { if (temp != -1) { rand = new Random(i * temp * unchecked((int)DateTime.Now.Ticks)); } int t = rand.Next(VcArray.Length - 1); if (temp != -1 && temp == t) { return CreateValidateNumber(length); } temp = t; num[i - 1] = VcArray[t]; } return num; } #endregion #region 生成图片验证码 /// <summary> /// 生成图片验证码 /// </summary> /// <param name="checkCode"></param> public static string CreateCheckCodeImage(string[] checkCode) { if (checkCode == null || checkCode.Length <= 0) return null; Bitmap image = new Bitmap((int)Math.Ceiling((checkCode.Length * 32.5)), 60); Graphics g = Graphics.FromImage(image); try { //生成随机生成器 Random random = new Random(); //清空图片背景色 g.Clear(Color.White); //定义颜色 Color[] c = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple }; //画图片的背景噪音线 for (int i = 0; i < 25; i++) { int cindex = random.Next(7); int findex = random.Next(5); int x1 = random.Next(image.Width); int x2 = random.Next(image.Width); int y1 = random.Next(image.Height); int y2 = random.Next(image.Height); } //定义字体 string[] f = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋体" }; for (int k = 0; k <= checkCode.Length - 1; k++) { int cindex = random.Next(7); int findex = random.Next(5); Font drawFont = new Font(f[findex], 26, (System.Drawing.FontStyle.Bold)); SolidBrush drawBrush = new SolidBrush(c[cindex]); float x = 5.0F; float y = 0.0F; float width = 42.0F; float height = 48.0F; int sjx = random.Next(10); int sjy = random.Next(image.Height - (int)height); RectangleF drawRect = new RectangleF(x + sjx + (k * 25), y + sjy, width, height); StringFormat drawFormat = new StringFormat(); drawFormat.Alignment = StringAlignment.Center; g.DrawString(checkCode[k], drawFont, drawBrush, drawRect, drawFormat); } //画图片的前景噪音点 for (int i = 0; i < 500; i++) { int x = random.Next(image.Width); int y = random.Next(image.Height); image.SetPixel(x, y, Color.FromArgb(random.Next())); } int cindex1 = random.Next(7); //画图片的边框线 g.DrawRectangle(new Pen(c[cindex1]), 0, 0, image.Width - 1, image.Height - 1); MemoryStream ms = new MemoryStream(); image.Save(ms, ImageFormat.Jpeg); //return ms.ToArray(); // 图片到byte[]再到base64string的转换： string base64pic = "data:image/jpeg;base64,"+ Convert.ToBase64String(ms.ToArray()); return base64pic; } finally { g.Dispose(); image.Dispose(); } } #endregion }
控制器的代码：
#region 随机生成sessionid /// <summary> /// 随机生成sessionid /// </summary> private string sessionId { get { return "__sessionName__" + Guid.NewGuid().ToString(); } } #endregion #region 登录页面 /// <summary> /// 登录页面 /// </summary> /// <returns></returns> public ActionResult Login() { ViewBag.sessionid = sessionId;//传到页面，放在隐藏域里面 return View(); } #endregion #region 生成验证码 /// <summary> /// 生成验证码 /// </summary> /// <param name="sessionid">随机的编码</param> /// <returns></returns> [HttpGet] public JsonResult CheckCode(string sessionid) { //生成验证码 string[] str = ValidateCode.CreateValidateNumber(4); string strcode = string.Empty; for (int i = 0; i < str.Length; i++) { strcode += str[i]; } string base64Pic = ValidateCode.CreateCheckCodeImage(str); RedisHelper redisHelper = new RedisHelper(); if (redisHelper.IsConnected() && !String.IsNullOrEmpty(sessionid)) { redisHelper.StringSet(sessionid, strcode, new TimeSpan(0, 10, 0));//有效期10分钟 } return Json(base64Pic, JsonRequestBehavior.AllowGet); } #endregion #region 登录 /// <summary> /// 登录 /// </summary> /// <param name="name">用户名</param> /// <param name="pwd">密码</param> /// <param name="isRemember">是否记住用户名</param> /// <param name="verifycode">验证码</param> /// <returns></returns> [HttpPost] public ActionResult Login(string name, string pwd, string verifycode, string sessionid) { string redisCheckCode = string.Empty; RedisHelper redisHelper = new RedisHelper(); if (redisHelper.IsConnected() && !string.IsNullOrEmpty(sessionid)) { redisCheckCode = redisHelper.StringGet(sessionid); } !string.IsNullOrEmpty(redisCheckCode) && verifycode.ToUpper() == redisCheckCode.ToUpper() } #endregion
Html：
<div id="verifycodeWrapper" class="mgt20"> <input maxlength="4" id="txtVerifycode" type="text" class="input-code" name="verifycode" placeholder="验证码" required="required" /> <img id="imgCode" alt="单击可刷新" style="height:35px;" onclick="ChangeCode()" /> </div> <input type="hidden" id="sessionid" name="sessionid" value="@ViewBag.sessionid">
JS:
//单击重新改变验证码 function ChangeCode() { var seid = '@ViewBag.sessionid'; $.ajax({ url: "/Home/CheckCode", type: "get", dataType: "json", contentType: "application/json", data: { sessionid: seid}, success: function (data) { if (data) { var img = document.getElementById("imgCode"); img.setAttribute("src", data); } } }); } $(document).ready(function () { setTimeout(ChangeCode(),5000); });
71. web api 自动生成文档
1).swagger集成。
2). apidoc，参考：http://apidocjs.com/#install http://apidoc.tools/#docs
npm install apidoc -g
apidoc -i controllers -o dest 具体如下:
72. ORM 框架 sqlsugar
js 模板框架 arttemplate
前端 sui.js
73.WebAPI防篡改签名验证抽象基类Attribute
/// <summary> /// WebAPI防篡改签名验证抽象基类Attribute /// </summary> public class AuthenticationAttribute : ActionFilterAttribute { //获取Asp.Net对应的Request /// <summary> /// Occurs before the action method is invoked. /// </summary> /// <param name="actionContext">The action context</param> public override void OnActionExecuting(HttpActionContext actionContext) { //Referer请求头验证 if(actionContext.Request==null || actionContext.Request.Headers==null || actionContext.Request.Headers.Referrer == null || string.IsNullOrWhiteSpace(actionContext.Request.Headers.Referrer.ToString())) { actionContext.Response = actionContext.Request.CreateResponse(HttpStatusCode.Unauthorized, "非法调用"); return; } var Referer = ConfigurationManager.AppSettings["Referer"]; if (string.IsNullOrWhiteSpace(Referer)) { return; } var flag = false; var list = Referer.Split(';'); foreach (var item in list) { if (actionContext.Request.Headers.Referrer.ToString().Contains(item)) { flag = true; break; } } if (!flag) { actionContext.Response = actionContext.Request.CreateResponse(HttpStatusCode.Unauthorized, "非法调用"); } } } public static class WebApiConfig { public static void Register(HttpConfiguration config) { config.Filters.Add(new AuthenticationAttribute()); } }
2).
public class DExceptionFilterAttribute : ExceptionFilterAttribute { public override void OnException(HttpActionExecutedContext context) { //可以记录一些日志 string fLog = context.Exception.StackTrace; DateTime EndTime = DateTime.Now; LogHelper.WriteError(string.Format("{0}调用出错结束时间:{1:yyyy-MM-dd HH:mm:ss:fff};\r\n出错的URL:<{2}>;\r\n报出的错误：{3}",context.Request.RequestUri.PathAndQuery,EndTime, context.Request.RequestUri.ToString(), fLog)); Action act = () => ErrorLogHelper.AddErrorLog(context, null, null); act.BeginInvoke(ar => act.EndInvoke(ar), null); context.Response = new HttpResponseMessage(HttpStatusCode.OK); context.Response.Content = new StringContent(JsonConvert.SerializeObject(new HISResponse() { Status = -1})); } } public static class WebApiConfig { public static void Register(HttpConfiguration config) { //加入异常过滤器,统一集中处理异常报错和异常日志记录,系统异常时统一返回的结果 config.Filters.Add(new DExceptionFilterAttribute()); } }
74.C#启动线程的几种方法
什么线程有几种启动方式，怎么优化sql语句，
Mvc页面生命周期
结构和类的区别，结构的作用
数据库的优化
.net core与mvc区别，有哪些优缺点
MVC 过滤器
75.linq 两个基础数据成对出现
linst.Where(p => && CodeList.Contains(p.Code)) .OrderByDescending(p => p.TestDate) .GroupBy(x => new { x.TestID, x.TestDate }) .Select(g => new { TestID = g.Key.TestID, TestDate = g.Key.TestDate, Count = g.Count() }).Where(g => g.Count == 2).OrderByDescending(p => p.TestDate).Take(30).ToList()
76. C# 将字符串转为int，否则返回默认值
/// <summary> /// 将字符串转为int，否则返回默认值 var ids = request.Data.HealthTypeIDs.Split(',').ToIntArray(); /// </summary> /// <param name="values"></param> /// <returns></returns> public static int[] ToIntArray(this string[] values) { int len = values.Length; var indexIds = new int[len]; for (int i = 0; i < len; i++) { indexIds[i] = values[i].ToInt(0); } return indexIds; }
77.List<int> 的结果集，除了用循环，怎么转为List<string>的结果集
int[] id = new int[] { 1, 2, 3, 4, 5, 6, 7 }; var ids = id.ToList(); List<string> ArryIds = new List<string>(); ArryIds = ids.ConvertAll<string>(x => x.ToString());
或
ArryIds = new List<string>(ids.Select(x => x.ToString()));
1.List<string> 转 List<int> var strList = new List<string>{"1","2","3"}; var intList = strList.Select<string,int>(x =>Convert.ToInt32(x)); 2.List<string> 转 List<long> var strList = new List<string>{"1","2","3"}; var longList = strList.Select<string,long>(x =>Convert.ToInt64(x));
78.优化查询，可以用SQL把结果集查出来（toList()),然后在分组(GroupBy)
79.C# switch case 的优化方式
#region 1的性别转换2的性别 /// <summary> /// 1性别转换2的性别 /// </summary> /// <param name="sex">性别 (0:男,1女)</param> /// <returns></returns> private string SexTGender(int? sex) { //性别[1:男,2:女,0:未知的性别,9:未说明的性别] string gender = "9"; if (sex.HasValue) { switch (sex.Value) { case 0: gender = "1"; break; case 1: gender = "2"; break; } } return gender; } #endregion
调用如下：
var person = new PersonModel(); MemberModel request = new MemberModel(); person.Gender = SexTGender(request.sex);
可以使用反射来改造
#region 实体转换 /// <summary> /// 实体转换 /// </summary> /// <typeparam name="T">目标实体</typeparam> /// <typeparam name="S">源实体</typeparam> /// <param name="t">目标实体</param> /// <param name="s">源实体</param> /// <param name="tfiled">目标具体实体字段</param> /// <param name="sfield">源具体实体字段</param> /// <param name="dic">字典项</param> public static void mapToField<T, S>(T t, S s, string tfiled, string sfield, Dictionary<string, string> dic) { var tt = typeof(T); var tf = tt.GetProperty(tfiled); var ts = typeof(S); var sf = ts.GetProperty(sfield); var v = sf.GetValue(s).ToString(); var n_v = dic.Where(a => a.Key == v).FirstOrDefault().Value; tf.SetValue(t, n_v); } #endregion
调用，这样实现的方式不用每次转换都要写一个方法
var person = new PersonModel(); MemberModel request = new MemberModel(); Dictionary<string, string> dic = new Dictionary<string, string>(); if (request.sex.HasValue) { //key 性别 (0:男,1女) //value 性别[1:男,2:女,0:未知的性别,9:未说明的性别] dic.Add("0", "1"); dic.Add("1", "2"); mapToField<PersonModel, MemberModel>(person, request, "Gender", "sex", dic); }
80.C# unity https://www.cnblogs.com/chenyucong/p/6272600.html
81.C# 实现redis 分布式锁 ,另外的实现：https://www.oddity.cn/6190714.html
https://www.php.cn/redis/436811.html
需要引入Redlock.CSharp.dll 和RedLock.dll
public class RedlockHelper { public void Lock(Action<bool> action, string val, string key = "IdNo") { Redlock.CSharp.Redlock dlm = new Redlock.CSharp.Redlock(RedisConnectionHelp.Instance); Lock lockObject; string resourceName = string.Format("Redlock_{0}_{1}", key, val); var locked = dlm.Lock(resourceName, new TimeSpan(0, 0, 10), out lockObject); try { action.Invoke(locked); } finally { if (lockObject != null) dlm.Unlock(lockObject); } } }
调用：
new RedlockHelper().Lock((locked) => { if (locked) { ID = obj.addTest(); } });
82.sql server 通过创建存储过程，生成表对应的model
1).创建一个类别表
CREATE TABLE [dbo].[Catalogue]( [CatalogueId] [int] IDENTITY(1,1) NOT NULL, [Name] [nvarchar](126) NOT NULL, [Description] [varchar](256) NULL, [ParentCatalogueId] [int] NOT NULL, [CreatedTime] [datetime] NOT NULL, [ModifiedTime] [datetime] NOT NULL, [IsDeleted] [bit] NOT NULL, PRIMARY KEY CLUSTERED ( [CatalogueId] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO ALTER TABLE [dbo].[Catalogue] ADD DEFAULT (NULL) FOR [Description] GO ALTER TABLE [dbo].[Catalogue] ADD DEFAULT ('0') FOR [ParentCatalogueId] GO ALTER TABLE [dbo].[Catalogue] ADD DEFAULT ('0') FOR [IsDeleted] GO EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'类别Id' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'Catalogue', @level2type=N'COLUMN',@level2name=N'CatalogueId' GO EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'类别名称' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'Catalogue', @level2type=N'COLUMN',@level2name=N'Name' GO EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'描述' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'Catalogue', @level2type=N'COLUMN',@level2name=N'Description' GO EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'父类别ID' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'Catalogue', @level2type=N'COLUMN',@level2name=N'ParentCatalogueId' GO EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'创建时间' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'Catalogue', @level2type=N'COLUMN',@level2name=N'CreatedTime' GO EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'修改时间' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'Catalogue', @level2type=N'COLUMN',@level2name=N'ModifiedTime' GO EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'是否删除,0:否,1:是' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'Catalogue', @level2type=N'COLUMN',@level2name=N'IsDeleted' GO EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'产品类别' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'Catalogue' GO
2).创建存储过程
============================================= --表结构生成model -- ============================================= CREATE PROCEDURE [dbo].[Sys_ViewModel] @TableName nvarchar(64), @KeyWord nvarchar(64) AS BEGIN SELECT CASE WHEN col.colorder = 1 THEN obj.name ELSE @TableName END AS 表名, '/// <summary>' as lie1, '///'+CONVERT(nvarchar(50), ISNULL(ep.[value], '')) as lie2, '/// </summary>'as lie3, ' public ' + CASE WHEN t.name = 'bigint' THEN 'int' WHEN t.name = 'nvarchar' THEN 'string'
WHEN t.name = 'varchar' THEN 'string'
WHEN t.name = 'int' THEN 'int' WHEN t.name = 'bit' THEN 'bool' WHEN t.name='datetime' THEN 'DateTime' WHEN t.name='tinyint' THEN 'int' else t.name END +' '+col.name +' { get; set; }' as lie4 into #Temp FROM dbo.syscolumns col LEFT JOIN dbo.systypes t ON col.xtype = t.xusertype inner JOIN dbo.sysobjects obj ON col.id = obj.id AND obj.xtype = 'U' AND obj.status >= 0 LEFT JOIN dbo.syscomments comm ON col.cdefault = comm.id LEFT JOIN sys.extended_properties ep ON col.id = ep.major_id AND col.colid = ep.minor_id AND ep.name = 'MS_Description' LEFT JOIN sys.extended_properties epTwo ON obj.id = epTwo.major_id AND epTwo.minor_id = 0 AND epTwo.name = 'MS_Description' WHERE obj.name = @TableName--表名 AND col.name LIKE '%'+@KeyWord+'%' ORDER BY col.colorder ; declare @lie0 nvarchar(50), @lie1 nvarchar(50), @lie2 nvarchar(50), @lie3 nvarchar(50), @lie4 nvarchar(50) declare mycursor cursor for select* from #Temp open mycursor while 1=1 begin fetch next from mycursor into @lie0,@lie1,@lie2,@lie3,@lie4 if @@fetch_status <>0 break print @lie1+char(10)+@lie2+char(10)+@lie3+char(10)+@lie4+char(13); end close mycursor; deallocate mycursor; END
3). 调用存储过程
exec Sys_ViewModel 'Catalogue',''
83.get set 的理解：https://www.jb51.net/article/37960.htm
84. 站点目录下怎么指定favicon.ico图标， <link rel="icon" href="~/favicontest1.ico">
85. 详解C#中==、Equals、ReferenceEquals的区别
86. var where = new StringBuilder(30, 30 * itemId.Length); //设置合适的初始长度，可以显著提高效率（避免了多次内存申请）
87. 使用C#实现字符串反转算法，例如：输入"12345", 输出"54321"
public static string Reverse(string str) { if (string.IsNullOrEmpty(str)) { throw new ArgumentException("参数不合法"); } StringBuilder sb = new StringBuilder(str.Length); //注意：设置合适的初始长度，可以显著提高效率（避免了多次内存申请） for (int index = str.Length - 1; index >= 0; index--) { sb.Append(str[index]); } return sb.ToString(); } public static string Reverse(string str) { if (string.IsNullOrEmpty(str)) { throw new ArgumentException("参数不合法"); } char[] chars = str.ToCharArray(); int begin = 0; int end = chars.Length - 1; char tempChar; while (begin < end) { tempChar = chars[begin]; chars[begin] = chars[end]; chars[end] = tempChar; begin++; end--; } string strResult = new string(chars); return strResult; } 还有一个比较简单也挺有效的方法： public static string Reverse(string str) { char[] arr = str.ToCharArray(); Array.Reverse(arr); return new string(arr); }
88. 布式id生成器: https://juejin.im/post/5d8882d8f265da03e369c063 https://www.cnblogs.com/shiningrise/p/5727895.html
89.C# 获取时间戳 参考：https://www.cnblogs.com/rainman/p/4810043.html
public static int ToTimeStamp(this DateTime time) { DateTime startTime = TimeZone.CurrentTimeZone.ToLocalTime(new DateTime(1970, 1, 1)); var result = (int)(time - startTime).TotalSeconds; return result; } public static long ToJavascriptTimestamp(this DateTime input) { var reuslt = ((input - new DateTime(1970, 1, 1, 0, 0, 0, 0)).Ticks / 10000); //毫秒 return reuslt; }
var currentTime = DateTime.Now;//2019/10/8 16:17:15 var result1 = DateTimeExtend.ToTimeStamp(currentTime);//1570522635 var result2 = DateTimeExtend.ToJavascriptTimestamp(currentTime);//1570551435012
对比js
var currentTime = new Date('2019/10/8 16:17:15'); var result1 = Date.parse(currentTime);//1570522635000 var result2 = currentTime.valueOf();//1570522635000 var result3 = currentTime.getTime();//1570522635000
90.AutoMapper和EmitMapper
91.full join isnull
92.IQueryable 是在把筛选的条件都转为SQL语句在数据库查询时直接筛选。
IEnumerable 是在数据库中把整张表查出来保存在内存中，再进行筛选。
参考：https://blog.csdn.net/qq_43146253/article/details/88123610
93.C# linq 匿名类型（IQueryable）转为DaTable
public static class IQueryableExtend { public static DataTable ToDataTable<T>(this IQueryable<T> varlist) { //定义要返回的DataTable对象 DataTable dtReturn = new DataTable(); // 保存列集合的属性信息数组 PropertyInfo[] oProps = null; if (varlist == null) return dtReturn;//安全性检查 //循环遍历集合，使用反射获取类型的属性信息 foreach (T rec in varlist) { //使用反射获取T类型的属性信息，返回一个PropertyInfo类型的集合 if (oProps == null) { oProps = ((Type)rec.GetType()).GetProperties(); //循环PropertyInfo数组 foreach (PropertyInfo pi in oProps) { Type colType = pi.PropertyType;//得到属性的类型 //如果属性为泛型类型 if ((colType.IsGenericType) && (colType.GetGenericTypeDefinition() == typeof(Nullable<>))) { //获取泛型类型的参数 colType = colType.GetGenericArguments()[0]; } //将类型的属性名称与属性类型作为DataTable的列数据 dtReturn.Columns.Add(new DataColumn(pi.Name, colType)); } } //新建一个用于添加到DataTable中的DataRow对象 DataRow dr = dtReturn.NewRow(); //循环遍历属性集合 foreach (PropertyInfo pi in oProps) { //为DataRow中的指定列赋值 dr[pi.Name] = pi.GetValue(rec, null) == null ? DBNull.Value : pi.GetValue(rec, null); } //将具有结果值的DataRow添加到DataTable集合中 dtReturn.Rows.Add(dr); } return dtReturn;//返回DataTable对象 } }
调用方：
using (DBEntities db = new DBEntities()) { var query = from tes in db.Test select new { testNo = tes.testNo, Name = tes.Name, testDate = tes.testDate, }; if (!string.IsNullOrWhiteSpace(dto.UserID)) { query = query.Where(t => t.UserID == dto.UserID); } query = query.OrderBy(t => t.testDate); return query.ToDataTable(); }
94. C# 集合类 有哪些是线程安全的，哪些不是线程安全的？
ArryList此类型的公共静态成员是线程安全的。 但不保证所有实例成员都是线程安全的。
Hashtable 是线程安全的，可供多个读取器线程和单个写入线程使用。
List<T> : 此类型的公共静态成员是线程安全的。但不保证所有实例成员都是线程安全的
Dictionary<TKey,TValue>:只要没有修改集合，Dictionary<TKey,TValue> 就可以同时支持多个读取器。 尽管如此，枚举集合本身并不是一个线程安全的过程。 在具有写入访问的枚举竞争的罕见情况下，必须在整个枚举过程中锁定集合。 若要允许多个线程访问集合以进行读写操作，则必须实现自己的同步。
https://docs.microsoft.com/zh-cn/dotnet/standard/collections/thread-safe/
95.前端js 调用后台web api 显示图片验证码
[HttpGet] public FileResult VerifyCode() { byte[] vr = null; return new FileContentResult(vr, "image/png"); } var url = 'VerifyCode'; var xmlhttp; xmlhttp = new XMLHttpRequest(); xmlhttp.open("get", url, true); xmlhttp.responseType = "blob"; xmlhttp.setRequestHeader("Content-Type", "application/json"); xmlhttp.onload = function () { if (this.status == 200) { var blob = this.response; var img = document.getElementById("imgCode"); img.onload = function (e) { window.URL.revokeObjectURL(img.src); }; img.src = window.URL.createObjectURL(blob); } } xmlhttp.send();
//图片到byte[]再到base64string的转换： [HttpGet] public JsonResult CheckCode() { string base64pic = "data:image/jpeg;base64,"+ Convert.ToBase64String(ms.ToArray());//为二进制字节流 return Json(base64Pic, JsonRequestBehavior.AllowGet); } $.ajax({ url: "CheckCode", type: "get", dataType: "json", contentType: "application/json", success: function (data) { if (data) { var img = document.getElementById("imgCode"); img.setAttribute("src", data); } } });
96.前端js 调用后台url return "test.aspx?r=" + (new Date()).getTime();
97.http下 Chrome浏览器无权限调用摄像头麦克风的解决方法：https://www.xfei.me/index.php?c=article&id=159
98.对话框弹出事件
shown.bs.modal事件 要先于页面值的绑定,反之show.bs.modal
具体参考：https://v3.bootcss.com/javascript/#popovers
99.http下 Chrome浏览器无权限调用摄像头麦克风的解决方法
"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --unsafely-treat-insecure-origin-as-secure="http://test.com:49581" --user-data-dir=C:\tmp
99. asp.net mvc 和 asp.net web api 下载文件流（这里以视频举例）
asp.net web api(.net framework支持，.net core 不支持): #region 视频查看 /// <summary> /// 视频查看 /// </summary> /// <param name="no">请求参数</param> /// <returns></returns> [Route("~/Video/{no}")] [HttpGet] public HttpResponseMessage DownloadVideo(string no) { HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK); byte[] vedio = null;//自己获取二进制字节流 if (vedio == null) { result.Content = new StringContent("没有相关的视频记录！"); return result; } result.Content = new ByteArrayContent(vedio); result.Content.Headers.ContentType = new MediaTypeHeaderValue("video/mp4"); //result.Content.Headers.Add("Content-Disposition", $"attachment;filename=\"{ Guid.NewGuid().ToString("N") }.mp4\""); result.Headers.CacheControl = new CacheControlHeaderValue(); result.Headers.CacheControl.Public = true; result.Headers.CacheControl.MaxAge = TimeSpan.FromSeconds(120); result.Content.Headers.Expires = DateTimeOffset.Now.AddSeconds(120); return result; } #endregion asp.net mvc(.net framework和.net core 都支持): #region 打开视频 /// <summary> /// 打开视频 /// </summary> /// <param name="no">请求参数</param> /// <returns></returns> [HttpGet] [Route("~/Video")] public ActionResult GetVideo([FromQuery] string no) { byte[] files = null; if (string.IsNullOrEmpty(recordNo)) { ContentResult result = new ContentResult(); result.Content = "请求参数不能为空"; return result; } else { byte[] files = null;//自己获取二进制字节流 } if (files == null || files.Length == 0) { ContentResult result = new ContentResult(); result.Content = "没有相关的视频记录"; return result; } return File(files.ToArray(), "video/mpeg4", $"{Guid.NewGuid().ToString("N")}.mp4"); } #endregion
#region 下载 /// <summary> /// 下载资源 /// </summary> /// <param name="url"></param> /// <returns></returns> public static byte[] DownloadData(string url) { try { var client = new WebClient(); var byteData = client.DownloadData(url); return byteData; } catch { return null; } } /// <summary> /// 下载资源 /// </summary> /// <param name="url"></param> /// <returns></returns> public static async Task<byte[]> DownloadFile(string url) { using (var client = new HttpClient()) { var uri = new Uri(url); byte[] urlContents = await client.GetByteArrayAsync(uri); return urlContents; } } #endregion
页面打开视频需要给src赋值，关闭的时候要把src值清空
<div id="video" class="easyui-dialog" title="视频播放" style="width:700px;height:750px;overflow: hidden;" data-options="resizable:false,closed:true,modal:true,onClose:function(){ $('#video video').prop('src', ''); }"> <video src="" autoplay controls="controls" width="100%" height="100%" poster="~/Content/images/loading.gif" style="background:black;"></video> <h1 style="display:none; margin-top: 100px; width: 100%; text-align: center;font-size:20px;">未找到相应的视频资源</h1> </div> function playVideo(channelId) { var url = '/Common/JumpWlyy?url=' + '/Video/' + Id; $("#video").children().hide().filter("video").show(); $("#video video").prop("src", url); $('#video').window('open'); }
100.批量修改图片名称，去掉文件名中的中文字符
/// <summary> /// 批量修改文件名"001测试.jpg"(去掉测试),调用ModifyFileName("D:\\pictor"); /// </summary> /// <param name="path">文件夹zhi路径</param> private void ModifyFileName(string path) { string chineseStr = "[\u4e00-\u9fa5]";//中文正则 foreach (string childPath in Directory.GetDirectories(path)) { ModifyFileName(childPath); } foreach (var childPath in Directory.GetFiles(path)) { string fileName = Path.GetFileName(childPath); //匹配字符串中包含中文字符的正则表达式 if (!string.IsNullOrEmpty(fileName) && Regex.IsMatch(fileName, chineseStr) { string newFileName = Regex.Replace(fileName, chineseStr, ""); string newPath = Path.GetDirectoryName(childPath) + "\\" + newFileName; System.IO.File.Move(childPath, newPath); } } }
101.
var id = 1;
using (DBEntities db = new DBEntities())
{
var test1 = db.Tests.Where(x => x.id == id && !x.IsDel);
var test2 = db.Tests.Where(x => x.id == id && x.IsDel == false);//推荐使用这个写法
}
解析：test2的写法要好些
test1 生成对应的sql select * from Tests where id = 1 and IsDel <> 1 //该表给IsDel建了索引，会导致索引失效
test2 生成对应的sql select * from Tests where id = 1 and IsDel = 0 ////该表给IsDel建了索引，索引能起到作用
102.
if（str1.ToLower()==str2.ToLower()） //这种方式会产生新的字符串，不推荐 if（string. Compare(str1,str2,true)） //这种方式性能更好
103. C# 枚举，继承int 有什么作用？
默认情况下，枚举成员的关联常数值为类型 int；它们从零开始，并按定义文本顺序递增 1。 可以显式指定任何其他整数数值类型作为枚举类型的基础类型。 还可以显式指定关联的常数值。
https://docs.microsoft.com/zh-cn/dotnet/csharp/language-reference/builtin-types/enum
默认就是Int 如果值不超过256可以继承byte， 节省存储空间。就像定义一个 class 默认继承 object 一样。
由默认的 int 改为占空间更小的 byte，可以节省空间……
写继承int ,可读性好些，也让其他人知道可以继承byte 等类型。不写表示遵从约定，写了表示明确使用默认值。
枚举默认是 int类型，当然如果是其它基础类型，可以写继承关键字，如 byte, sbyte, ushort, long等。
104. GRPC 用于http 2.0 google的远程过程调用
