CodeDomProvider.IsDefinedExtension(String) 方法

定义

测试文件扩展名是否在计算机上配置了关联的 CodeDomProvider 实现。Tests whether a file name extension has an associated CodeDomProvider implementation configured on the computer.

public:
 static bool IsDefinedExtension(System::String ^ extension);
public static bool IsDefinedExtension (string extension);
[System.Runtime.InteropServices.ComVisible(false)]
public static bool IsDefinedExtension (string extension);
static member IsDefinedExtension : string -> bool
[<System.Runtime.InteropServices.ComVisible(false)>]
static member IsDefinedExtension : string -> bool
Public Shared Function IsDefinedExtension (extension As String) As Boolean

参数

extension
String

文件扩展名。A file name extension.

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 falsetrue if a CodeDomProvider implementation is configured for the specified file name extension; otherwise, false.

属性

例外

extensionnullThe extension is null.

调用方没有所要求的权限。The caller does not have the required permission.

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。The following code example determines the CodeDomProvider implementation for an input file name extension and displays the configured settings for the language provider. 此代码示例是为类提供的更大示例的一部分 CompilerInfoThis code example is part of a larger example provided for the CompilerInfo class.

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.object > 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 CodeDomProviderThe <system.codedom> Element in the machine configuration file (Machine.config) contains the language provider and compiler configuration settings for each CodeDomProvider implementation on the computer. IsDefinedExtension方法在提供程序配置元素中搜索指定的文件扩展名。The IsDefinedExtension method searches the provider configuration elements for the specified file name extension.

文件扩展名不区分大小写。File name extensions are case-insensitive.

适用于

另请参阅