T4运行时模板

可以通过Visual Studio运行时文本模板在您的应用程序在运行时生成文本字符串。 执行应用程序的计算机不必具有 Visual Studio。 运行库模板有时称为"预处理文本模板"由于在编译时，该模板会生成运行时执行的代码。

将现有文件转换为运行时模板：

• 将该文件的“自定义工具”属性设置为 TextTemplatingFilePreprocessor。【文本模板的自定义工具是TextTemplatingFileGenerator】
• 在文件开头插入下面的行 <#@ template language="C#" #>

运行时模板的tt的内容如下：

 <#@ template language="C#" #>
 <#@ assembly name="System.Core" #>
 <#@ import namespace="System.Linq" #>
 <#@ import namespace="System.Text" #>
 <#@ import namespace="System.Collections.Generic" #>

 <h2>Sales figures</h2>
 <table>
 <# foreach (var item in m_data)
    // m_data is declared in MyWebPageCode.cs
    { #>
       <tr><td> <#= item.Key #> </td>
           <td> <#= item.Value #> </td></tr>
 <# } // end of foreach
 #>
 </table>

效果如下：

 // ------------------------------------------------------------------------------
 // <auto-generated>
 //     此代码由工具生成。
 //     运行时版本: 12.0.0.0
 //
 //     对此文件的更改可能会导致不正确的行为。此外，如果
 //     重新生成代码，这些更改将会丢失。
 // </auto-generated>
 // ------------------------------------------------------------------------------
 namespace Test
 {
     using System.Linq;
     using System.Text;
     using System.Collections.Generic;
     using System;

     /// <summary>
     /// Class to produce the template output
     /// </summary>

     #line 1 "F:\study\share\Test\html.tt"
     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.TextTemplating", "12.0.0.0")]
     public partial class html : htmlBase
     {
 #line hidden
         /// <summary>
         /// Create the template output
         /// </summary>
         public virtual string TransformText()
         {
             this.Write("<table>\r\n    ");

             #line 7 "F:\study\share\Test\html.tt"
  for (int i = 1; i <= 10; i++)
        { 

             #line default
             #line hidden
             this.Write("         <tr><td>Test name ");

             #line 9 "F:\study\share\Test\html.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(i));

             #line default
             #line hidden
             this.Write(" </td>\r\n             <td>Test value ");

             #line 10 "F:\study\share\Test\html.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(i * i));

             #line default
             #line hidden
             this.Write(" </td> </tr>\r\n    ");

             #line 11 "F:\study\share\Test\html.tt"
  } 

             #line default
             #line hidden
             this.Write(" </table>");
             return this.GenerationEnvironment.ToString();
         }
     }

     #line default
     #line hidden
     #region Base class
     /// <summary>
     /// Base class for this transformation
     /// </summary>
     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.TextTemplating", "12.0.0.0")]
     public class htmlBase
     {
         #region Fields
         private global::System.Text.StringBuilder generationEnvironmentField;
         private global::System.CodeDom.Compiler.CompilerErrorCollection errorsField;
         private global::System.Collections.Generic.List<int> indentLengthsField;
         private string currentIndentField = "";
         private bool endsWithNewline;
         private global::System.Collections.Generic.IDictionary<string, object> sessionField;
         #endregion
         #region Properties
         /// <summary>
         /// The string builder that generation-time code is using to assemble generated output
         /// </summary>
         protected System.Text.StringBuilder GenerationEnvironment
         {
             get
             {
                 if ((this.generationEnvironmentField == null))
                 {
                     this.generationEnvironmentField = new global::System.Text.StringBuilder();
                 }
                 return this.generationEnvironmentField;
             }
             set
             {
                 this.generationEnvironmentField = value;
             }
         }
         /// <summary>
         /// The error collection for the generation process
         /// </summary>
         public System.CodeDom.Compiler.CompilerErrorCollection Errors
         {
             get
             {
                 if ((this.errorsField == null))
                 {
                     this.errorsField = new global::System.CodeDom.Compiler.CompilerErrorCollection();
                 }
                 return this.errorsField;
             }
         }
         /// <summary>
         /// A list of the lengths of each indent that was added with PushIndent
         /// </summary>
         private System.Collections.Generic.List<int> indentLengths
         {
             get
             {
                 if ((this.indentLengthsField == null))
                 {
                     this.indentLengthsField = new global::System.Collections.Generic.List<int>();
                 }
                 return this.indentLengthsField;
             }
         }
         /// <summary>
         /// Gets the current indent we use when adding lines to the output
         /// </summary>
         public string CurrentIndent
         {
             get
             {
                 return this.currentIndentField;
             }
         }
         /// <summary>
         /// Current transformation session
         /// </summary>
         public virtual global::System.Collections.Generic.IDictionary<string, object> Session
         {
             get
             {
                 return this.sessionField;
             }
             set
             {
                 this.sessionField = value;
             }
         }
         #endregion
         #region Transform-time helpers
         /// <summary>
         /// Write text directly into the generated output
         /// </summary>
         public void Write(string textToAppend)
         {
             if (string.IsNullOrEmpty(textToAppend))
             {
                 return;
             }
             // If we're starting off, or if the previous text ended with a newline,
             // we have to append the current indent first.
             if (((this.GenerationEnvironment.Length == 0)
                         || this.endsWithNewline))
             {
                 this.GenerationEnvironment.Append(this.currentIndentField);
                 this.endsWithNewline = false;
             }
             // Check if the current text ends with a newline
             if (textToAppend.EndsWith(global::System.Environment.NewLine, global::System.StringComparison.CurrentCulture))
             {
                 this.endsWithNewline = true;
             }
             // This is an optimization. If the current indent is "", then we don't have to do any
             // of the more complex stuff further down.
             if ((this.currentIndentField.Length == 0))
             {
                 this.GenerationEnvironment.Append(textToAppend);
                 return;
             }
             // Everywhere there is a newline in the text, add an indent after it
             textToAppend = textToAppend.Replace(global::System.Environment.NewLine, (global::System.Environment.NewLine + this.currentIndentField));
             // If the text ends with a newline, then we should strip off the indent added at the very end
             // because the appropriate indent will be added when the next time Write() is called
             if (this.endsWithNewline)
             {
                 this.GenerationEnvironment.Append(textToAppend, 0, (textToAppend.Length - this.currentIndentField.Length));
             }
             else
             {
                 this.GenerationEnvironment.Append(textToAppend);
             }
         }
         /// <summary>
         /// Write text directly into the generated output
         /// </summary>
         public void WriteLine(string textToAppend)
         {
             this.Write(textToAppend);
             this.GenerationEnvironment.AppendLine();
             this.endsWithNewline = true;
         }
         /// <summary>
         /// Write formatted text directly into the generated output
         /// </summary>
         public void Write(string format, params object[] args)
         {
             this.Write(string.Format(global::System.Globalization.CultureInfo.CurrentCulture, format, args));
         }
         /// <summary>
         /// Write formatted text directly into the generated output
         /// </summary>
         public void WriteLine(string format, params object[] args)
         {
             this.WriteLine(string.Format(global::System.Globalization.CultureInfo.CurrentCulture, format, args));
         }
         /// <summary>
         /// Raise an error
         /// </summary>
         public void Error(string message)
         {
             System.CodeDom.Compiler.CompilerError error = new global::System.CodeDom.Compiler.CompilerError();
             error.ErrorText = message;
             this.Errors.Add(error);
         }
         /// <summary>
         /// Raise a warning
         /// </summary>
         public void Warning(string message)
         {
             System.CodeDom.Compiler.CompilerError error = new global::System.CodeDom.Compiler.CompilerError();
             error.ErrorText = message;
             error.IsWarning = true;
             this.Errors.Add(error);
         }
         /// <summary>
         /// Increase the indent
         /// </summary>
         public void PushIndent(string indent)
         {
             if ((indent == null))
             {
                 throw new global::System.ArgumentNullException("indent");
             }
             this.currentIndentField = (this.currentIndentField + indent);
             this.indentLengths.Add(indent.Length);
         }
         /// <summary>
         /// Remove the last indent that was added with PushIndent
         /// </summary>
         public string PopIndent()
         {
             string returnValue = "";
             if ((this.indentLengths.Count > 0))
             {
                 int indentLength = this.indentLengths[(this.indentLengths.Count - 1)];
                 this.indentLengths.RemoveAt((this.indentLengths.Count - 1));
                 if ((indentLength > 0))
                 {
                     returnValue = this.currentIndentField.Substring((this.currentIndentField.Length - indentLength));
                     this.currentIndentField = this.currentIndentField.Remove((this.currentIndentField.Length - indentLength));
                 }
             }
             return returnValue;
         }
         /// <summary>
         /// Remove any indentation
         /// </summary>
         public void ClearIndent()
         {
             this.indentLengths.Clear();
             this.currentIndentField = "";
         }
         #endregion
         #region ToString Helpers
         /// <summary>
         /// Utility class to produce culture-oriented representation of an object as a string.
         /// </summary>
         public class ToStringInstanceHelper
         {
             private System.IFormatProvider formatProviderField  = global::System.Globalization.CultureInfo.InvariantCulture;
             /// <summary>
             /// Gets or sets format provider to be used by ToStringWithCulture method.
             /// </summary>
             public System.IFormatProvider FormatProvider
             {
                 get
                 {
                     return this.formatProviderField ;
                 }
                 set
                 {
                     if ((value != null))
                     {
                         this.formatProviderField  = value;
                     }
                 }
             }
             /// <summary>
             /// This is called from the compile/run appdomain to convert objects within an expression block to a string
             /// </summary>
             public string ToStringWithCulture(object objectToConvert)
             {
                 if ((objectToConvert == null))
                 {
                     throw new global::System.ArgumentNullException("objectToConvert");
                 }
                 System.Type t = objectToConvert.GetType();
                 System.Reflection.MethodInfo method = t.GetMethod("ToString", new System.Type[] {
                             typeof(System.IFormatProvider)});
                 if ((method == null))
                 {
                     return objectToConvert.ToString();
                 }
                 else
                 {
                     return ((string)(method.Invoke(objectToConvert, new object[] {
                                 this.formatProviderField })));
                 }
             }
         }
         private ToStringInstanceHelper toStringHelperField = new ToStringInstanceHelper();
         /// <summary>
         /// Helper to produce culture-oriented representation of an object as a string
         /// </summary>
         public ToStringInstanceHelper ToStringHelper
         {
             get
             {
                 return this.toStringHelperField;
             }
         }
         #endregion
     }
     #endregion
 }

 class Program
     {
         static void Main(string[] args)
         {
             html html = new html();
             System.IO.File.WriteAllText("outputPage.html", html.TransformText());
             Console.ReadKey();
         }  

     }
 结果：

 <table>
              <tr><td>Test name 1 </td>
              <td>Test value 1 </td> </tr>
              <tr><td>Test name 2 </td>
              <td>Test value 4 </td> </tr>
              <tr><td>Test name 3 </td>
              <td>Test value 9 </td> </tr>
              <tr><td>Test name 4 </td>
              <td>Test value 16 </td> </tr>
              <tr><td>Test name 5 </td>
              <td>Test value 25 </td> </tr>
              <tr><td>Test name 6 </td>
              <td>Test value 36 </td> </tr>
              <tr><td>Test name 7 </td>
              <td>Test value 49 </td> </tr>
              <tr><td>Test name 8 </td>
              <td>Test value 64 </td> </tr>
              <tr><td>Test name 9 </td>
              <td>Test value 81 </td> </tr>
              <tr><td>Test name 10 </td>
              <td>Test value 100 </td> </tr>
      </table>

若要在特定命名空间中放置已生成的类，请设置文本模板文件的“自定义工具命名空间”属性。

如果希望模板代码引用 .NET 或其他程序集（如 System.Xml.dll），应以常规方式将其添加到项目的“引用”中。

如果要以与 using 语句相同的方式导入命名空间，可以使用 import 指令

<#@ import namespace="System.Xml" #>

如果要在几个模板间共享文本，可以将文本放置在一个单独的文件中，然后在需要这些文本的每个文件中包含这些文本：

<#@include file="CommonHeader.txt" #> 

继承模式：基方法中的片段

• 基类在类功能块<#+...#>中定义方法
• 派生类可以调用基类中定义的方法

MyTextTemplate1.tt继承自SharedFragments.tt(生成的类MyTextTemplate1.cs 继承自SharedFragments.cs)

 SharedFragments.tt
 <#@ template language="C#" #>
 <#@ assembly name="System.Core" #>
 <#@ import namespace="System.Linq" #>
 <#@ import namespace="System.Text" #>
 <#@ import namespace="System.Collections.Generic" #>

 <#+
 protected void SharedText(int n)
 {
 #>
    Shared Text <#= n #>
 <#+
 }
 // Insert more methods here if required.
 #>

 SharedFragments.cs
 // ------------------------------------------------------------------------------
 // <auto-generated>
 //     此代码由工具生成。
 //     运行时版本: 12.0.0.0
 //
 //     对此文件的更改可能会导致不正确的行为。此外，如果
 //     重新生成代码，这些更改将会丢失。
 // </auto-generated>
 // ------------------------------------------------------------------------------
 namespace Test
 {
     using System.Linq;
     using System.Text;
     using System.Collections.Generic;
     using System;

     /// <summary>
     /// Class to produce the template output
     /// </summary>

     #line 1 "F:\study\share\Test\SharedFragments.tt"
     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.TextTemplating", "12.0.0.0")]
     public partial class SharedFragments : SharedFragmentsBase
     {
 #line hidden
         /// <summary>
         /// Create the template output
         /// </summary>
         public virtual string TransformText()
         {
             this.Write(" \r\n");
             return this.GenerationEnvironment.ToString();
         }

         #line 7 "F:\study\share\Test\SharedFragments.tt"

 protected void SharedText(int n)
 {

         #line default
         #line hidden

         #line 10 "F:\study\share\Test\SharedFragments.tt"
 this.Write("   Shared Text ");

         #line default
         #line hidden

         #line 11 "F:\study\share\Test\SharedFragments.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(n));

         #line default
         #line hidden

         #line 11 "F:\study\share\Test\SharedFragments.tt"
 this.Write("\r\n");

         #line default
         #line hidden

         #line 12 "F:\study\share\Test\SharedFragments.tt"

 }
 // Insert more methods here if required.

         #line default
         #line hidden
     }

     #line default
     #line hidden
     #region Base class
     /// <summary>
     /// Base class for this transformation
     /// </summary>
     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.TextTemplating", "12.0.0.0")]
     public class SharedFragmentsBase
     {
         #region Fields
         private global::System.Text.StringBuilder generationEnvironmentField;
         private global::System.CodeDom.Compiler.CompilerErrorCollection errorsField;
         private global::System.Collections.Generic.List<int> indentLengthsField;
         private string currentIndentField = "";
         private bool endsWithNewline;
         private global::System.Collections.Generic.IDictionary<string, object> sessionField;
         #endregion
         #region Properties
         /// <summary>
         /// The string builder that generation-time code is using to assemble generated output
         /// </summary>
         protected System.Text.StringBuilder GenerationEnvironment
         {
             get
             {
                 if ((this.generationEnvironmentField == null))
                 {
                     this.generationEnvironmentField = new global::System.Text.StringBuilder();
                 }
                 return this.generationEnvironmentField;
             }
             set
             {
                 this.generationEnvironmentField = value;
             }
         }
         /// <summary>
         /// The error collection for the generation process
         /// </summary>
         public System.CodeDom.Compiler.CompilerErrorCollection Errors
         {
             get
             {
                 if ((this.errorsField == null))
                 {
                     this.errorsField = new global::System.CodeDom.Compiler.CompilerErrorCollection();
                 }
                 return this.errorsField;
             }
         }
         /// <summary>
         /// A list of the lengths of each indent that was added with PushIndent
         /// </summary>
         private System.Collections.Generic.List<int> indentLengths
         {
             get
             {
                 if ((this.indentLengthsField == null))
                 {
                     this.indentLengthsField = new global::System.Collections.Generic.List<int>();
                 }
                 return this.indentLengthsField;
             }
         }
         /// <summary>
         /// Gets the current indent we use when adding lines to the output
         /// </summary>
         public string CurrentIndent
         {
             get
             {
                 return this.currentIndentField;
             }
         }
         /// <summary>
         /// Current transformation session
         /// </summary>
         public virtual global::System.Collections.Generic.IDictionary<string, object> Session
         {
             get
             {
                 return this.sessionField;
             }
             set
             {
                 this.sessionField = value;
             }
         }
         #endregion
         #region Transform-time helpers
         /// <summary>
         /// Write text directly into the generated output
         /// </summary>
         public void Write(string textToAppend)
         {
             if (string.IsNullOrEmpty(textToAppend))
             {
                 return;
             }
             // If we're starting off, or if the previous text ended with a newline,
             // we have to append the current indent first.
             if (((this.GenerationEnvironment.Length == )
                         || this.endsWithNewline))
             {
                 this.GenerationEnvironment.Append(this.currentIndentField);
                 this.endsWithNewline = false;
             }
             // Check if the current text ends with a newline
             if (textToAppend.EndsWith(global::System.Environment.NewLine, global::System.StringComparison.CurrentCulture))
             {
                 this.endsWithNewline = true;
             }
             // This is an optimization. If the current indent is "", then we don't have to do any
             // of the more complex stuff further down.
             if ((this.currentIndentField.Length == ))
             {
                 this.GenerationEnvironment.Append(textToAppend);
                 return;
             }
             // Everywhere there is a newline in the text, add an indent after it
             textToAppend = textToAppend.Replace(global::System.Environment.NewLine, (global::System.Environment.NewLine + this.currentIndentField));
             // If the text ends with a newline, then we should strip off the indent added at the very end
             // because the appropriate indent will be added when the next time Write() is called
             if (this.endsWithNewline)
             {
                 this.GenerationEnvironment.Append(textToAppend, , (textToAppend.Length - this.currentIndentField.Length));
             }
             else
             {
                 this.GenerationEnvironment.Append(textToAppend);
             }
         }
         /// <summary>
         /// Write text directly into the generated output
         /// </summary>
         public void WriteLine(string textToAppend)
         {
             this.Write(textToAppend);
             this.GenerationEnvironment.AppendLine();
             this.endsWithNewline = true;
         }
         /// <summary>
         /// Write formatted text directly into the generated output
         /// </summary>
         public void Write(string format, params object[] args)
         {
             this.Write(string.Format(global::System.Globalization.CultureInfo.CurrentCulture, format, args));
         }
         /// <summary>
         /// Write formatted text directly into the generated output
         /// </summary>
         public void WriteLine(string format, params object[] args)
         {
             this.WriteLine(string.Format(global::System.Globalization.CultureInfo.CurrentCulture, format, args));
         }
         /// <summary>
         /// Raise an error
         /// </summary>
         public void Error(string message)
         {
             System.CodeDom.Compiler.CompilerError error = new global::System.CodeDom.Compiler.CompilerError();
             error.ErrorText = message;
             this.Errors.Add(error);
         }
         /// <summary>
         /// Raise a warning
         /// </summary>
         public void Warning(string message)
         {
             System.CodeDom.Compiler.CompilerError error = new global::System.CodeDom.Compiler.CompilerError();
             error.ErrorText = message;
             error.IsWarning = true;
             this.Errors.Add(error);
         }
         /// <summary>
         /// Increase the indent
         /// </summary>
         public void PushIndent(string indent)
         {
             if ((indent == null))
             {
                 throw new global::System.ArgumentNullException("indent");
             }
             this.currentIndentField = (this.currentIndentField + indent);
             this.indentLengths.Add(indent.Length);
         }
         /// <summary>
         /// Remove the last indent that was added with PushIndent
         /// </summary>
         public string PopIndent()
         {
             string returnValue = "";
             if ((this.indentLengths.Count > ))
             {
                 int indentLength = this.indentLengths[(this.indentLengths.Count - )];
                 this.indentLengths.RemoveAt((this.indentLengths.Count - ));
                 if ((indentLength > ))
                 {
                     returnValue = this.currentIndentField.Substring((this.currentIndentField.Length - indentLength));
                     this.currentIndentField = this.currentIndentField.Remove((this.currentIndentField.Length - indentLength));
                 }
             }
             return returnValue;
         }
         /// <summary>
         /// Remove any indentation
         /// </summary>
         public void ClearIndent()
         {
             this.indentLengths.Clear();
             this.currentIndentField = "";
         }
         #endregion
         #region ToString Helpers
         /// <summary>
         /// Utility class to produce culture-oriented representation of an object as a string.
         /// </summary>
         public class ToStringInstanceHelper
         {
             private System.IFormatProvider formatProviderField  = global::System.Globalization.CultureInfo.InvariantCulture;
             /// <summary>
             /// Gets or sets format provider to be used by ToStringWithCulture method.
             /// </summary>
             public System.IFormatProvider FormatProvider
             {
                 get
                 {
                     return this.formatProviderField ;
                 }
                 set
                 {
                     if ((value != null))
                     {
                         this.formatProviderField  = value;
                     }
                 }
             }
             /// <summary>
             /// This is called from the compile/run appdomain to convert objects within an expression block to a string
             /// </summary>
             public string ToStringWithCulture(object objectToConvert)
             {
                 if ((objectToConvert == null))
                 {
                     throw new global::System.ArgumentNullException("objectToConvert");
                 }
                 System.Type t = objectToConvert.GetType();
                 System.Reflection.MethodInfo method = t.GetMethod("ToString", new System.Type[] {
                             typeof(System.IFormatProvider)});
                 if ((method == null))
                 {
                     return objectToConvert.ToString();
                 }
                 else
                 {
                     return ((string)(method.Invoke(objectToConvert, new object[] {
                                 this.formatProviderField })));
                 }
             }
         }
         private ToStringInstanceHelper toStringHelperField = new ToStringInstanceHelper();
         /// <summary>
         /// Helper to produce culture-oriented representation of an object as a string
         /// </summary>
         public ToStringInstanceHelper ToStringHelper
         {
             get
             {
                 return this.toStringHelperField;
             }
         }
         #endregion
     }
     #endregion
 }

 MyTextTemplate1.tt
 <#@ template language="C#" inherits="SharedFragments" #>
 begin
     <#SharedText() ;#>
 end 

 MyTextTemplate1.cs
 // ------------------------------------------------------------------------------
 // <auto-generated>
 //     此代码由工具生成。
 //     运行时版本: 12.0.0.0
 //
 //     对此文件的更改可能会导致不正确的行为。此外，如果
 //     重新生成代码，这些更改将会丢失。
 // </auto-generated>
 // ------------------------------------------------------------------------------
 namespace Test
 {
     using System;

     /// <summary>
     /// Class to produce the template output
     /// </summary>

     #line 1 "F:\study\share\Test\MyTextTemplate1.tt"
     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.TextTemplating", "12.0.0.0")]
     public partial class MyTextTemplate1 : SharedFragments
     {
 #line hidden
         /// <summary>
         /// Create the template output
         /// </summary>
         public override string TransformText()
         {
             this.Write("begin 1\r\n    ");

             #line 3 "F:\study\share\Test\MyTextTemplate1.tt"
 SharedText() ;

             #line default
             #line hidden
             this.Write("end 1\r\n");
             return this.GenerationEnvironment.ToString();
         }
     }

     #line default
     #line hidden
 }

使用 T4 文本模板的运行时文本生成