HttpWebRequest.UserAgent 属性

定义

命名空间:

System.Net

程序集:

System.Net.Requests.dll

Source:

HttpWebRequest.cs

获取或设置 User-agent HTTP 标头的值。

public:
 property System::String ^ UserAgent { System::String ^ get(); void set(System::String ^ value); };

public string? UserAgent { get; set; }

member this.UserAgent : string with get, set

Public Property UserAgent As String

属性值

String

User-agent HTTP 标头的值。 默认值为 null。

示例

下面的代码示例设置 UserAgent 属性。

// Create a new 'HttpWebRequest' object to the mentioned URL.
HttpWebRequest^ myHttpWebRequest = (HttpWebRequest^)( WebRequest::Create( "http://www.contoso.com" ) );
myHttpWebRequest->UserAgent = ".NET Framework Test Client";
// Assign the response object of 'HttpWebRequest' to a 'HttpWebResponse' variable.
HttpWebResponse^ myHttpWebResponse = (HttpWebResponse^)( myHttpWebRequest->GetResponse() );
// Display the contents of the page to the console.
Stream^ streamResponse = myHttpWebResponse->GetResponseStream();
StreamReader^ streamRead = gcnew StreamReader( streamResponse );
array<Char>^ readBuff = gcnew array<Char>(256);
int count = streamRead->Read( readBuff, 0, 256 );
Console::WriteLine( "\nThe contents of HTML Page are :\n" );
while ( count > 0 )
{
   String^ outputData = gcnew String( readBuff,0,count );
   Console::Write( outputData );
   count = streamRead->Read( readBuff, 0, 256 );
}
streamRead->Close();
streamResponse->Close();
myHttpWebResponse->Close();

// Create a new 'HttpWebRequest' object to the mentioned URL.
HttpWebRequest myHttpWebRequest=(HttpWebRequest)WebRequest.Create("http://www.contoso.com");
myHttpWebRequest.UserAgent=".NET Framework Test Client";
// Assign the response object of 'HttpWebRequest' to a 'HttpWebResponse' variable.
HttpWebResponse myHttpWebResponse=(HttpWebResponse)myHttpWebRequest.GetResponse();
// Display the contents of the page to the console.
Stream streamResponse=myHttpWebResponse.GetResponseStream();
StreamReader streamRead = new StreamReader( streamResponse );
Char[] readBuff = new Char[256];
int count = streamRead.Read( readBuff, 0, 256 );
Console.WriteLine("\nThe contents of HTML Page are :\n");	
while (count > 0)
{
    String outputData = new String(readBuff, 0, count);
    Console.Write(outputData);
    count = streamRead.Read(readBuff, 0, 256);
}
// Release the response object resources.
streamRead.Close();
streamResponse.Close();
myHttpWebResponse.Close();

 ' Create a new 'HttpWebRequest' object to the mentioned URL.
  Dim myHttpWebRequest As HttpWebRequest = CType(WebRequest.Create("http://www.contoso.com"), HttpWebRequest)
  myHttpWebRequest.UserAgent= ".NET Framework Test Client"
  ' The response object of 'HttpWebRequest' is assigned to a 'HttpWebResponse' variable.
  Dim myHttpWebResponse As HttpWebResponse = CType(myHttpWebRequest.GetResponse(), HttpWebResponse)
  ' Display the contents of the page to the console.
  Dim streamResponse As Stream = myHttpWebResponse.GetResponseStream()
  Dim streamRead As New StreamReader(streamResponse)
  Dim readBuff(256) As [Char]
  Dim count As Integer = streamRead.Read(readBuff, 0, 256)
  Console.WriteLine(ControlChars.Cr + "The contents of HTML Page are :" + ControlChars.Cr)
  While count > 0
      Dim outputData As New [String](readBuff, 0, count)
      Console.Write(outputData)
      count = streamRead.Read(readBuff, 0, 256)
  End While
  streamRead.Close()
   streamResponse.Close()    
' Release the response object resources.
   myHttpWebResponse.Close()

注解

谨慎

WebRequest、HttpWebRequest、ServicePoint和 WebClient 已过时，不应将其用于新开发。 请改用 HttpClient。

此属性的值存储在 WebHeaderCollection中。 如果设置了 WebHeaderCollection，则属性值将丢失。