1 Razor模板引擎的使用：
（1）常用三种模板引擎：
Razor 解释执行，微软内置、有提示，与JavaScript存在兼容性；
Nvelocity / Vtemplate 运行时动态执行，（比Razor更好）。
（2）Razor引擎的使用：
<!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> <title></title> </head> <body> <h1>胡安定</h1> <div> <h2>@Model.Name</h2> <h2>@Model.Age</h2> </div> <div> <ul> @for (var i = 0; i < 10;i++ ) { <li>@i</li> } </ul> </div> </body> </html>
using RazorEngine; using System; using System.Collections.Generic; using System.IO; using System.Linq; using System.Web; namespace Web_Cassini.Day8 { /// <summary> /// razor1 的摘要说明 /// </summary> public class razor1 : IHttpHandler { public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/html"; string path = context.Server.MapPath("~/Day8/razor1.cshtml"); string cshtml = File.ReadAllText(path); string cacheName=path + File.GetLastWriteTime(path); //文件全名+文件最后修改时间，作为缓存名，保证一旦修改缓存名改变，需要重新编译生成新的程序集 string html = Razor.Parse(cshtml, new { Name = "yzk", Age = 33 }, cacheName); //把cshtml解析为html context.Response.Write(html); } public bool IsReusable { get { return false; } } } }
（3）Razor引擎的原理：
每次Razor引擎对cshtml页面字符串 进行解析时，都会进行编译生成新的程序集，
设定cacheName后，只要cshtml页面不发送修改，则razor解析时不会再生成新的程序集。这样就降低内存的占用和时间的消耗。
using RazorEngine; using System; using System.Collections.Generic; using System.IO; using System.Linq; using System.Reflection; using System.Text; using System.Threading.Tasks; namespace Console_razor { class Program { static void Main(string[] args) { //把这个cshtml解析10次 for (int i = 0; i < 10;i++ ) { string path = @"F:\VisualStudio_example\ExamOneself\Console_Core\Web_Cassini\Day8\razor1.cshtml"; string cshtml = File.ReadAllText(path); //string html = Razor.Parse(path, null); string cacheName = path + File.GetLastWriteTime(path); //只要文件未修改，则缓存不会改变 string html = Razor.Parse(cshtml, new { Name = "yzk", Age = 33 }, cacheName); Console.WriteLine(html); Console.ReadKey(); } //输出解析10次过程中产生的所有程序集 Assembly[] asses = AppDomain.CurrentDomain.GetAssemblies(); foreach(Assembly ass in asses ) { Console.WriteLine(ass.FullName+"\r\n"); //发现：如果没有缓存，则每次解析都编译生成新的程序集。占用内存并消耗大量时间。 //所以：需要缓存，只要文件未修改，则缓存不会改变，再次解析就不用再编译生成新的程序集。 } Console.ReadKey(); } } }
2 Razor封装和调用外部方法
Razor封装单独将Razor解析cshtml写为一个广泛应用的方法。
Razor外部方法：HtmlEncodedString(htmlstring) ---> 将html字符串加密后显示；
RawString(htmlstring) ---> 将html字符串原样输出。
public class RazorHelper { /// <summary> /// Razor解析cshtml页面，并输出到浏览器 /// </summary> /// <param name="context">上下文</param> /// <param name="cshtmlVirtualPath">cshtml页面的虚拟路径</param> /// <param name="data">传递的虚拟实例</param> public static void RazorParse(HttpContext context, string cshtmlVirtualPath, object data) { string fullPath = context.Server.MapPath(cshtmlVirtualPath); string cshtml = File.ReadAllText(fullPath); string cacheName = fullPath + File.GetLastWriteTime(fullPath); string html = Razor.Parse(cshtml, data, cacheName); context.Response.Write(html); } /// <summary> /// 对html进行加密 /// </summary> /// <param name="htmlStr">html标签</param> /// <returns>加密之后的字符串</returns> public static HtmlEncodedString HtmlEncodedString(string htmlStr) { return new HtmlEncodedString(htmlStr); } /// <summary> /// 对html原样显示 /// </summary> /// <param name="htmlStr">html标签</param> /// <returns>html原来样子</returns> public static RawString RawString(string htmlStr) { return new RawString(htmlStr); } }
3 封装HTML标签中的<CheckBox>
/// <summary> /// 拼接生成CheckBox标签 /// </summary> /// <param name="name">name属性的值</param> /// <param name="id">id属性的值</param> /// <param name="isCheck">是否选中</param> /// <returns>CheckBox标签</returns> public static RawString CheckBox(string name, string id, bool isCheck) { StringBuilder sb = new StringBuilder(); sb.Append("<input type='checkbox' name='").Append(name).Append("' id='").Append(id).Append("' "); if(isCheck) { sb.Append("checked"); } sb.AppendLine(" />"); return new RawString(sb.ToString()); }
4 如果@后面的表达式是string类型，则cshtml会自动进行Encoded编码输出。
public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/html"; bool gender=true; RazorHelper.RazorParse(context, "~/Day8/razorHtml.cshtml", new { Gender = gender, Html ="List<T>就是一个集合",Text="<input type='text'/>"}); }
<body>
<div>
@Console_Core.Common.RazorHelper.CheckBox("gender","gender",@Model.Gender)
</div>
<div>
@Console_Core.Common.RazorHelper.RawString(Model.Html) <br />
@Console_Core.Common.RazorHelper.RawString(Model.Text) <br />
</div>
</body>
5 封装html标签中的<DropDownList>
int i=10,j=10; bool f1=i==j; //true
object obj1=i,obj2=j; bool f2=obj1==obj2; //false ==> 值类型到引用类型，涉及到装箱，装箱之后是2个不同对象
bool f3=object.equal(obj1,obj2); //true
bool f4=obj1.equal(obj2); //true ==> equal就是把两个的值进行比较
所以：引用类型的比较需要用equal函数。
/// <summary> /// 拼接生成DropDownList下拉列表 标签 /// </summary> /// <param name="list">实例的集合</param> /// <param name="valuePropName">实际的值属性的名称：比如，Id</param> /// <param name="textPropName">显示的文本属性的名称：比如，Name</param> /// <param name="selectedValue">选中的值</param> /// <param name="extendProperties">扩展属性的对象：比如，new {id='managerId',name='manager',style='color:red' }</param> /// <returns>DropDownList下拉列表 标签</returns> public static RawString DropDownList(IEnumerable list,string valuePropName,string textPropName,object selectedValue,object extendProperties) { //<select name='' id='' > //<option value=''> </option> //</select> StringBuilder sb = new StringBuilder(); sb.Append("<select "); #region 拼接扩展属性 Type extType = extendProperties.GetType(); PropertyInfo[] props = extType.GetProperties(); foreach (PropertyInfo prop in props) { string extPropName = prop.Name; object extPropValue = prop.GetValue(extendProperties); sb.Append(" ").Append(extPropName).Append("='").Append(extPropValue).Append("' "); } #endregion sb.AppendLine(" >"); #region 拼接下拉选项 foreach (object item in list) { Type itemType = item.GetType(); PropertyInfo itemValueProp = itemType.GetProperty(valuePropName); object valuePropValue = itemValueProp.GetValue(item); PropertyInfo itemTextProp = itemType.GetProperty(textPropName); object textPropValue = itemTextProp.GetValue(item); sb.Append("<option value='").Append(valuePropValue).Append("' "); if(object.Equals(valuePropValue,selectedValue)) //如果当前值与选中的值相等，则selected （引用类型用equal，如果用=则是不同的实例，因为发生过装箱） { sb.Append(" selected "); } sb.Append(">").Append(textPropValue).AppendLine(" </option> "); } #endregion sb.AppendLine("</select>"); return new RawString(sb.ToString()); }
<div> @Console_Core.Common.RazorHelper.DropDownList(Model.Persons.list,Model.Persons.valuePropName,Model.Persons.textPropName,Model.Persons.PersonId,new { id = "managerId", name = "manager", style = "color:red" }) <br /> </div>
public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/html"; bool gender=true; List<Person> list = new List<Person>() { new Person() { Id = 1, Name = "yzk" }, new Person() { Id = 2, Name = "rupeng" } }; RazorHelper.RazorParse(context, "~/Day8/razorHtml.cshtml", new { Gender = gender, Html = "List<T>就是一个集合", Text = "<input type='text'/>", Persons = new { list = list, valuePropName = "Id", textPropName = "Name", PersonId=2 } }); } public class Person { public int Id { get; set; } public string Name { get; set; } }
6 总结---> 完整的 RazorHelper.cs
using System; using System.Collections; using System.Collections.Generic; using System.IO; using System.Linq; using System.Reflection; using System.Text; using System.Threading.Tasks; using System.Web; using RazorEngine; using RazorEngine.Text; namespace Console_Core.Common { public class RazorHelper { /// <summary> /// Razor解析cshtml页面，并输出到浏览器 /// </summary> /// <param name="context">上下文</param> /// <param name="cshtmlVirtualPath">cshtml页面的虚拟路径</param> /// <param name="data">传递的虚拟实例</param> public static void RazorParse(HttpContext context, string cshtmlVirtualPath, object data) { string fullPath = context.Server.MapPath(cshtmlVirtualPath); string cshtml = File.ReadAllText(fullPath); string cacheName = fullPath + File.GetLastWriteTime(fullPath); string html = Razor.Parse(cshtml, data, cacheName); context.Response.Write(html); } /// <summary> /// 对html进行加密 /// </summary> /// <param name="htmlStr">html标签</param> /// <returns>加密之后的字符串</returns> public static HtmlEncodedString HtmlEncodedString(string htmlStr) { return new HtmlEncodedString(htmlStr); } /// <summary> /// 对html原样显示 /// </summary> /// <param name="htmlStr">html标签</param> /// <returns>html原来样子</returns> public static RawString RawString(string htmlStr) { return new RawString(htmlStr); } /// <summary> /// 拼接生成CheckBox 标签 /// </summary> /// <param name="isCheck">是否选中</param> /// <param name="extendProperties">扩展属性的对象：比如，new {id='managerId',name='manager',style='color:red' }</param> /// <returns>CheckBox标签</returns> public static RawString CheckBox(bool isCheck, object extendProperties) { StringBuilder sb = new StringBuilder(); sb.Append("<input type='checkbox' "); sb.Append(RenderExtProperties(extendProperties)); if(isCheck) { sb.Append(" checked "); } sb.AppendLine(" />"); return new RawString(sb.ToString()); } /// <summary> /// 拼接扩展属性 及对应的值 /// </summary> /// <param name="extendProperties">扩展属性 所在的匿名实例</param> /// <returns>拼接生成的 包含属性名和值 的字符串： 比如，“ name='manager' id='managerId' ” </returns> private static string RenderExtProperties(object extendProperties) { StringBuilder sb = new StringBuilder(); #region 拼接扩展属性 Type extType = extendProperties.GetType(); PropertyInfo[] props = extType.GetProperties(); foreach (PropertyInfo prop in props) { string extPropName = prop.Name; object extPropValue = prop.GetValue(extendProperties); sb.Append(" ").Append(extPropName).Append("='").Append(extPropValue).Append("' "); } #endregion return sb.ToString(); } /// <summary> /// 拼接生成DropDownList下拉列表 标签 /// </summary> /// <param name="list">实例的集合</param> /// <param name="valuePropName">实际的值属性的名称：比如，Id</param> /// <param name="textPropName">显示的文本属性的名称：比如，Name</param> /// <param name="selectedValue">选中的值</param> /// <param name="extendProperties">扩展属性的对象：比如，new {id='managerId',name='manager',style='color:red' }</param> /// <returns>DropDownList下拉列表 标签</returns> public static RawString DropDownList(IEnumerable list,string valuePropName,string textPropName,object selectedValue,object extendProperties) { //<select name='' id='' > //<option value=''> </option> //</select> StringBuilder sb = new StringBuilder(); sb.Append("<select "); #region 拼接扩展属性 sb.Append(RenderExtProperties(extendProperties)); #endregion sb.AppendLine(" >"); #region 拼接下拉选项 foreach (object item in list) { object valuePropValue, textPropValue; GetvalueAndTextPropValue(item, valuePropName, textPropName, out valuePropValue, out textPropValue); sb.Append("<option value='").Append(valuePropValue).Append("' "); if(object.Equals(valuePropValue,selectedValue)) //如果当前值与选中的值相等，则selected （引用类型用equal，如果用=则是不同的实例，因为发生过装箱） { sb.Append(" selected "); } sb.Append(">").Append(textPropValue).AppendLine(" </option> "); } #endregion sb.AppendLine("</select>"); return new RawString(sb.ToString()); } /// <summary> /// 拼接生成RadioButtonList 标签 /// </summary> /// <param name="list">实例的集合</param> /// <param name="valuePropName">实际的值属性的名称：比如，Id</param> /// <param name="textPropName">显示的文本属性的名称：比如，Name</param> /// <param name="selectedValue">选中的值</param> // <param name="extendProperties">扩展属性的对象：比如，new {name='gender',style='color:red' }</param> /// <returns>RadioButtonList 标签</returns> public static RawString RadioButtonList(IEnumerable list, string valuePropName, string textPropName, object selectedValue, object extendProperties) { //<input type="radio" name="gender" value="1" checked /><label>男</label><br /> //只能单选 StringBuilder sb = new StringBuilder(); foreach(object item in list) { object valuePropValue, textPropValue; GetvalueAndTextPropValue(item, valuePropName, textPropName, out valuePropValue, out textPropValue); sb.Append("<input type=\"radio\" "); sb.Append(RenderExtProperties(extendProperties)); sb.Append(" value=\"").Append(valuePropValue).Append("\""); if(object.Equals(valuePropValue,selectedValue)) { sb.Append(" checked "); } sb.Append(" /><label>").Append(textPropValue).AppendLine("</label><br />"); } return new RawString(sb.ToString()); } /// <summary> /// 拼接生成CheckBoxList 标签 /// </summary> /// <param name="list">实例的集合</param> /// <param name="valuePropName">实际的值属性的名称：比如，Id</param> /// <param name="textPropName">显示的文本属性的名称：比如，Name</param> /// <param name="selectedValues">选中的值的数组</param> /// <param name="extendProperties">扩展属性的对象：比如，new {name='hobby',style='color:red' }</param> /// <returns>CheckBoxList 标签</returns> public static RawString CheckBoxList(IEnumerable list, string valuePropName, string textPropName, object[] selectedValues, object extendProperties) { //<input type="checkbox" name="hobby" value="1" checked /><label>足球</label><br /> //可多选 StringBuilder sb = new StringBuilder(); foreach(object item in list) { object valuePropValue,textPropValue; GetvalueAndTextPropValue(item, valuePropName, textPropName, out valuePropValue, out textPropValue); sb.Append("<input type=\"checkbox\" "); sb.Append(RenderExtProperties(extendProperties)); sb.Append (" value=\"").Append(valuePropValue).Append("\" "); if(selectedValues.Contains(valuePropValue)) { sb.Append(" checked "); } sb.Append(" /><label>").Append(textPropValue).AppendLine("</label><br />"); } return new RawString(sb.ToString()); } /// <summary> /// 根据指定实例的 值属性名和文本属性名 获得 值属性值和文本属性值 /// </summary> /// <param name="item">指定实例</param> /// <param name="valuePropName">值属性名</param> /// <param name="textPropName">文本属性名</param> /// <param name="valuePropValue">out 值属性值</param> /// <param name="textPropValue">out 文本属性值</param> private static void GetvalueAndTextPropValue(object item, string valuePropName, string textPropName, out object valuePropValue, out object textPropValue) { Type type = item.GetType(); PropertyInfo valueProp = type.GetProperty(valuePropName); valuePropValue = valueProp.GetValue(item); PropertyInfo textProp = type.GetProperty(textPropName); textPropValue = textProp.GetValue(item); } } }
<!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> <title></title> </head> <body> <div> @Console_Core.Common.RazorHelper.CheckBox(@Model.Gender, new { name="gender",id="genderId"}) </div> <div> @Console_Core.Common.RazorHelper.RawString(Model.Html) <br /> @Console_Core.Common.RazorHelper.RawString(Model.Text) <br /> </div> <div> @Console_Core.Common.RazorHelper.DropDownList(Model.Persons.list,Model.Persons.valuePropName,Model.Persons.textPropName,Model.Persons.PersonId,new { id = "managerId", name = "manager", style = "color:red" }) <br /> </div> <div> @*<input type="radio" name="gender" value="1" / checked><label>男</label><br />*@ @Console_Core.Common.RazorHelper.RadioButtonList(Model.Genders.list, Model.Genders.valuePropName, Model.Genders.textPropName, Model.Genders.selectedValue, new { name="gender",style = "color:blue" }) <br /> </div> <div> @*<input type="checkbox" name="hobby" value="1" checked /><label>足球</label><br />*@ @Console_Core.Common.RazorHelper.CheckBoxList(Model.Hobbys.list, Model.Hobbys.valuePropName, Model.Hobbys.textPropName, Model.Hobbys.selectedValues, new { name="hobby",style = "color:yellow" }) <br /> </div> </body> </html>
using System; using System.Collections.Generic; using System.Linq; using System.Web; using Console_Core.Common; namespace Web_Cassini.Day8 { /// <summary> /// razorHtml 的摘要说明 /// </summary> public class razorHtml : IHttpHandler { public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/html"; bool gender=true; List<Person> list = new List<Person>() { new Person() { Id = 1, Name = "yzk" }, new Person() { Id = 2, Name = "rupeng" } }; List<Gender> listGender = new List<Gender>() { new Gender() { Id = 1, Name = "男" }, new Gender() { Id = 2, Name = "女"},new Gender() { Id = 3, Name = "太监" }}; List<Hobby> listHobby = new List<Hobby>() { new Hobby() { Id = 1, Name = "足球" }, new Hobby() { Id = 2, Name = "篮球" }, new Hobby() { Id = 3, Name = "排球" } }; RazorHelper.RazorParse(context, "~/Day8/razorHtml.cshtml", new { Gender = gender, Html = "List<T>就是一个集合", Text = "<input type='text'/>", Persons = new { list = list, valuePropName = "Id", textPropName = "Name", PersonId=2 }, Genders = new { list = listGender, valuePropName = "Id", textPropName = "Name", selectedValue=2, }, Hobbys = new { list = listHobby, valuePropName = "Id", textPropName = "Name", selectedValues=new object[]{1,3} } }); } public class Person { public int Id { get; set; } public string Name { get; set; } } public class Gender { public int Id { get; set; } public string Name { get; set; } } public class Hobby { public int Id { get; set; } public string Name { get; set; } } public bool IsReusable { get { return false; } } } }
