CodeDomProvider.IsDefinedExtension(String) 方法

定义

命名空间:

System.CodeDom.Compiler

程序集:

System.CodeDom.dll

包:

System.CodeDom v8.0.0

Source:

CodeDomProvider.cs

测试文件扩展名是否在计算机上配置了关联的 CodeDomProvider 实现。

public:
 static bool IsDefinedExtension(System::String ^ extension);

public static bool IsDefinedExtension (string extension);

static member IsDefinedExtension : string -> bool

Public Shared Function IsDefinedExtension (extension As String) As Boolean

参数

extension

String

文件扩展名。

返回

Boolean

如果为指定的文件扩展名配置了 CodeDomProvider 实现，则为 true；否则，为 false。

例外

ArgumentNullException

extension 为 null。

SecurityException

调用方没有所要求的权限。

示例

下面的代码示例确定 CodeDomProvider 输入文件扩展名的实现，并显示语言提供程序的配置设置。 此代码示例是为 CompilerInfo 类提供的一个更大示例的一部分。

if (  !fileExtension->StartsWith(  "." ) )
   fileExtension = String::Concat( ".", fileExtension );

// Get the language associated with the file extension.
CodeDomProvider^ provider = nullptr;
if ( CodeDomProvider::IsDefinedExtension( fileExtension ) )
{
   String^ language = CodeDomProvider::GetLanguageFromExtension( fileExtension );
   if ( language )
      Console::WriteLine( "The language \"{0}\" is associated with file extension \"{1}\"\n",
                           language, fileExtension );

   // Check for a corresponding language provider.
   if ( language && CodeDomProvider::IsDefinedLanguage( language ) )
   {
      provider = CodeDomProvider::CreateProvider( language );
      if ( provider )
      {
         // Display information about this language provider.
         Console::WriteLine( "Language provider:  {0}\n", provider->ToString() );
         
         // Get the compiler settings for this language.
         CompilerInfo^ langCompilerInfo = CodeDomProvider::GetCompilerInfo( language );
         if ( langCompilerInfo )
         {
            CompilerParameters^ langCompilerConfig = langCompilerInfo->CreateDefaultCompilerParameters();
            if ( langCompilerConfig )
            {
               Console::WriteLine( "  Compiler options:        {0}", langCompilerConfig->CompilerOptions );
               Console::WriteLine( "  Compiler warning level:  {0}", langCompilerConfig->WarningLevel.ToString() );
            }
         }
      }
   }
}

if ( provider == nullptr )  // Tell the user that the language provider was not found.
   Console::WriteLine( "There is no language provider associated with input file extension \"{0}\".", fileExtension );

if (fileExtension[0] != '.')
{
    fileExtension = "." + fileExtension;
}

// Get the language associated with the file extension.
if (CodeDomProvider.IsDefinedExtension(fileExtension))
{
    CodeDomProvider provider;
    String language = CodeDomProvider.GetLanguageFromExtension(fileExtension);

    Console.WriteLine("The language \"{0}\" is associated with file extension \"{1}\"",
        language, fileExtension);
    Console.WriteLine();

    // Next, check for a corresponding language provider.

    if (CodeDomProvider.IsDefinedLanguage(language))
    {
        provider = CodeDomProvider.CreateProvider(language);

        // Display information about this language provider.

        Console.WriteLine("Language provider:  {0}",
            provider.ToString());
        Console.WriteLine();

        // Get the compiler settings for this language.

        CompilerInfo langCompilerInfo = CodeDomProvider.GetCompilerInfo(language);
        CompilerParameters langCompilerConfig = langCompilerInfo.CreateDefaultCompilerParameters();

        Console.WriteLine("  Compiler options:        {0}",
            langCompilerConfig.CompilerOptions);
        Console.WriteLine("  Compiler warning level:  {0}",
            langCompilerConfig.WarningLevel);
    }
}
else
{
    // Tell the user that the language provider was not found.
    Console.WriteLine("There is no language provider associated with input file extension \"{0}\".",
        fileExtension);
}

If Not fileExtension.StartsWith(".") Then
   fileExtension = "." + fileExtension
End If

' Get the language associated with the file extension.
If CodeDomProvider.IsDefinedExtension(fileExtension) Then
   Dim provider As CodeDomProvider
   Dim language As String = CodeDomProvider.GetLanguageFromExtension(fileExtension)
   
   Console.WriteLine("The language ""{0}"" is associated with file extension ""{1}""", _
       language, fileExtension)
   Console.WriteLine()
   
   ' Check for a corresponding language provider.
   If CodeDomProvider.IsDefinedLanguage(language) Then
      provider = CodeDomProvider.CreateProvider(language)
      
      ' Display information about this language provider.
      Console.WriteLine("Language provider:  {0}", _
         provider.ToString())
      Console.WriteLine()
      
      ' Get the compiler settings for this language.
      Dim langCompilerInfo As CompilerInfo = CodeDomProvider.GetCompilerInfo(language)
      Dim langCompilerConfig As CompilerParameters = langCompilerInfo.CreateDefaultCompilerParameters()
      
      Console.WriteLine("  Compiler options:        {0}", _
          langCompilerConfig.CompilerOptions)
      Console.WriteLine("  Compiler warning level:  {0}", _
          langCompilerConfig.WarningLevel)
   End If
Else
   ' Tell the user that the language provider was not found.
   Console.WriteLine("There is no language provider associated with input file extension ""{0}"".", fileExtension)
End If

注解

计算机配置文件中的 system.codedom> 元素 (Machine.config) 包含计算机上每个实现的语言提供程序和编译器配置设置。<CodeDomProvider 方法 IsDefinedExtension 在提供程序配置元素中搜索指定的文件扩展名。

文件扩展名不区分大小写。

另请参阅

• GetLanguageFromExtension(String)
• CreateProvider(String)
• 编译器和语言提供程序设置架构