常用小知识总结 .
1、在数字统计中，经常会遇到类似67.666666%等的显示问题，其实我们想要得到的是67.67%就可以了，但是我们用
val.ToString("F2")的话，那么100%就会显示成100.00%,不是很好看，怎么办呢？
以下介绍一种方法：
Math.Round(参数列表)方法
//实际得分占标准分比例
public string getPercent(string text1, string text2)
{
double t1,t2,result;
try
{
t1 = double.Parse(text1.Trim().ToString());
t2 = double.Parse(text2.Trim().ToString());
result = double.Parse(((t1 / t2) * 100).ToString());
}
catch(Exception)
{
ClientScript.RegisterClientScriptBlock(GetType(), "", "<script>alert('字符格式不正确');</script>");
return;
}
return Math.Round(result, 2, MidpointRounding.AwayFromZero).ToString()+"%";
}
2、很简单的一个倒计时，进入某个页面的方法
其实重点的就是利用JavaScript里的一个setInterval函数，下面写下该简单的额js脚本
<script type="text/javascript">
var time = 10;
function count() {
if (time > 0) {
document.getElementById("dzsj").innerHTML = time;
time--;
}
else if (time == 0) {
window.location.href = "CompanyNews/gsxw.aspx";
clearInterval(timer);
}
}
timer = setInterval('count()', 1000); //第一个是函数，需用' '引起来,第二个参数是毫秒值(11000
</script>
<div>
系统将在<span id="dzsj" style="font-weight: bold; color: Red;"></span>秒内跳转到公司新闻页面！
</div>
3、定时页面跳转
ClientScript.RegisterClientScriptBlock(GetType(), "", "<script>alert(/'响应启动成功!/');setTimeout(function(){location.href='URFeedBack.aspx'},1000); </script>");
4、鼠标经过时弹出图片,移出后消失的简单效果代码：
- html xmlns="http://www.w3.org/1999/xhtml"><head runat="server"> <title>无标题页</title> <mce:script type="text/javascript"><!-- function showImage(obj){ var e = e||window.event; var div = document.getElementById("Image"); var path = obj.innerHTML; div.innerHTML="<img src=""+path+"" mce_src=""+path+"" width='100' height='100'/>"; div.style.display="block"; div.style.top = e.clientY; div.style.left=e.clientX; } function hideImage(){ document.getElementById("Image").style.display="none"; } // --></mce:script></head><body> <form id="form1" runat="server"> <div id="Image" style="position:absolute;width:100px;height:100px;border:1px solid red;display:none;"></div> <div> <asp:DataList ID="DataList1" runat="server"> <HeaderTemplate><table></HeaderTemplate> <ItemTemplate> <tr> <td><span onmouseover="showImage(this)" onmouseout="hideImage()"><%#Eval("Path")%></span></td> <td><img src='<%#Eval("Path") %>' /></td> </tr> </ItemTemplate> <HeaderTemplate></table></HeaderTemplate> </asp:DataList> </div> </form></body></html>后台cs代码protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { DataList1.DataSource = getDataTable(); DataList1.DataBind(); } } public DataTable getDataTable() { string[] name = { "images/p002.jpg", "images/p003.jpg", "images/p004.jpg" }; DataTable dt = new DataTable(); dt.Columns.Add("ID", typeof(System.Int32)); dt.Columns.Add("Path", typeof(System.String)); for (int i = 0; i < name.Length; i++) { DataRow row = dt.NewRow(); row[0] = i + 1; row[1] = name[i]; dt.Rows.Add(row); } return dt; }
5、地址栏中传递int类型参数，为防止用户非法修改参数的一个解决办法：
- int type = 0;if(!int.TryParse(Request.QueryString["type"], out type){ Response.Write("不合法"); return;}
6、限时抢购代码
团购倒计时抢购功能（JS代码） JS代码如下：
<SCRIPT LANGUAGE="JavaScript">
function _fresh()
{
var endtime=new Date("2010/11/05,12:20:12");
var nowtime = new Date();
var leftsecond=parseInt((endtime.getTime()-nowtime.getTime())/1000);
__d=parseInt(leftsecond/3600/24);
__h=parseInt((leftsecond/3600)%24);
__m=parseInt((leftsecond/60)%60);
__s=parseInt(leftsecond%60);
document.getElementById("times").innerHTML=__d+"天 "+__h+"小时"+__m+"分"+__s+"秒";
if(leftsecond<=0){
document.getElementById("times").innerHTML="抢购已结束";
clearInterval(sh);
}
}
_fresh()
var sh;
sh=setInterval(_fresh,1000);
</SCRIPT>
Html代码如下：
<div id="content">
<h1>限时抢购啦！</h1>
<p>还剩<span id="times"></span></p>
</div>
7、字符串中中英文字符区分方法：
方法一：
string str = " 放不开放不下taken in and fetch off " ; string str1 = new string (str.ToList().Where(x => ((x >= ' A ' && x <= ' Z ' ) || (x >= ' a ' && x <= ' z ' ))).ToArray()); string str2 = str.Replace(str1, "" ); 方法二：
8、WPF中定义TabControl的样式： < Window x:Class = " CaseAnalysis_WPF_.Window1 " xmlns = " http://schemas.microsoft.com/winfx/2006/xaml/presentation " xmlns:x = " http://schemas.microsoft.com/winfx/2006/xaml " Title = " Window1 " Height = " 300 " Width = " 300 " > < Window.Resources > < Style TargetType = " {x:Type TabItem} " > < Setter Property = " Template " > < Setter.Value > < ControlTemplate TargetType = " {x:Type TabItem} " > < Grid > < Border Name = " Border " Background = " LightBlue " BorderBrush = " Black " BorderThickness = " 1,1,1,1 " CornerRadius = " 6,6,0,0 " > < ContentPresenter x:Name = " ContentSite " VerticalAlignment = " Center " HorizontalAlignment = " Center " ContentSource = " Header " Margin = " 12,2,12,2 " /> </ Border > </ Grid > < ControlTemplate.Triggers > < Trigger Property = " IsSelected " Value = " True " > < Setter TargetName = " Border " Property = " Background " Value = " Red " /> </ Trigger > < Trigger Property = " IsSelected " Value = " False " > < Setter TargetName = " Border " Property = " Background " Value = " LightGray " /> </ Trigger > </ ControlTemplate.Triggers > </ ControlTemplate > </ Setter.Value > </ Setter > </ Style > </ Window.Resources > < Grid > < TabControl HorizontalAlignment = " Left " Name = " tabControl1 " VerticalAlignment = " Top " Height = " 311 " Width = " 491 " TabStripPlacement = " Left " IsTextSearchEnabled = " False " IsManipulationEnabled = " False " Margin = " -2,0,0,0 " > < TabItem Name = " tab1 " UseLayoutRounding = " False " Background = " #FF41DBF7 " Width = " 25 " Height = " 60 " BorderBrush = " Black " Margin = " 0 " > </ TabItem > </ TabControl > </ Grid > </ Window >9、后台找前台html控件： System.Web.UI.HtmlControls.HtmlInputCheckBox cb = row.FindControl("checkboxItem") as System.Web.UI.HtmlControls.HtmlInputCheckBox; 10、数据绑定类型
（1）将HashTable数据源输出成一个数组，将该数组绑定；
（2）直接绑定，但是要指定DropDownList的Text和Value分别为HashTable的Key和Value。
例如：
Hashtable ht = new Hashtable(); for(int i=0; i<10; i++) { ht.Add(i+1,"Item"+1); } this.DropDownList1.DataSource = ht; this.DropDownList1.DataTextField = "key"; this.DropDownList1.DataValueField = "value"; this.DropDownList1.DataBind();
关于DataList与HashTable数据绑定其实也挺简单，只需将HashTable的Key或者Value与控件绑定即可，例如：
Hashtable ht = new Hashtable(); //对ht赋值 this.DataList1.DataSource = ht.Values; this.DataList1.DataBind();
