Szerkesztés

Megosztás a következőn keresztül:


WebRequest.Method Property

Definition

When overridden in a descendant class, gets or sets the protocol method to use in this request.

public:
 abstract property System::String ^ Method { System::String ^ get(); void set(System::String ^ value); };
public:
 virtual property System::String ^ Method { System::String ^ get(); void set(System::String ^ value); };
public abstract string Method { get; set; }
public virtual string Method { get; set; }
member this.Method : string with get, set
Public MustOverride Property Method As String
Public Overridable Property Method As String

Property Value

The protocol method to use in this request.

Exceptions

If the property is not overridden in a descendant class, any attempt is made to get or set the property.

Examples

The following example sets the Method property to POST to indicate that the request will post data to the target host.

#using <System.dll>

using namespace System;
using namespace System::Net;
using namespace System::IO;
using namespace System::Text;
using namespace System::Threading;
public ref class RequestState
{
public:

   // This class stores the request state of the request.
   WebRequest^ request;
   RequestState()
   {
      request = nullptr;
   }

};

ref class WebRequest_BeginGetRequeststream
{
public:
   static ManualResetEvent^ allDone = gcnew ManualResetEvent( false );
   static void ReadCallback( IAsyncResult^ asynchronousResult )
   {
      RequestState^ myRequestState = dynamic_cast<RequestState^>(asynchronousResult->AsyncState);
      WebRequest^ myWebRequest = myRequestState->request;
      
      // End of the Asynchronus request.
      Stream^ streamResponse = myWebRequest->EndGetRequestStream( asynchronousResult );
      
      // Create a string that is to be posted to the uri.
      Console::WriteLine( "Please enter a string to be posted:" );
      String^ postData = Console::ReadLine();
      
      // Convert  the string into a Byte array.
      array<Byte>^byteArray = Encoding::UTF8->GetBytes( postData );
      
      // Write data to the stream.
      streamResponse->Write( byteArray, 0, postData->Length );
      streamResponse->Close();
      allDone->Set();
   }

};

int main()
{
   
   // Create a new request to the mentioned URL.
   WebRequest^ myWebRequest = WebRequest::Create( "http://www.contoso.com" );
   
   // Create an instance of the RequestState and assign 'myWebRequest' to its request field.
   RequestState^ myRequestState = gcnew RequestState;
   myRequestState->request = myWebRequest;
   myWebRequest->ContentType = "application/x-www-form-urlencoded";
   
   // Set the 'Method' prperty  to 'POST' to post data to a Uri.
   myRequestState->request->Method = "POST";
   
   // Start the Asynchronous 'BeginGetRequestStream' method call.
   IAsyncResult^ r = dynamic_cast<IAsyncResult^>(myWebRequest->BeginGetRequestStream( gcnew AsyncCallback( WebRequest_BeginGetRequeststream::ReadCallback ), myRequestState ));
   WebRequest_BeginGetRequeststream::allDone->WaitOne();
   WebResponse^ myWebResponse = myWebRequest->GetResponse();
   Console::WriteLine( "The String* entered has been posted." );
   Console::WriteLine( "Please wait for the response..." );
   Stream^ streamResponse = myWebResponse->GetResponseStream();
   StreamReader^ streamRead = gcnew StreamReader( streamResponse );
   array<Char>^readBuff = gcnew array<Char>(256);
   int count = streamRead->Read( readBuff, 0, 256 );
   Console::WriteLine( "The contents of the HTML page are " );
   while ( count > 0 )
   {
      String^ outputData = gcnew String( readBuff,0,count );
      Console::Write( outputData );
      count = streamRead->Read( readBuff, 0, 256 );
   }

   streamResponse->Close();
   streamRead->Close();
   
   // Release the HttpWebResponse Resource.
   myWebResponse->Close();
}
using System;
using System.Net;
using System.IO;
using System.Text;
using System.Threading;

public class RequestState
{
    // This class stores the request state of the request.
    public WebRequest request;    
    public RequestState()
    {
        request = null;
    }
}

class WebRequest_BeginGetRequeststream
{
    public static ManualResetEvent allDone= new ManualResetEvent(false);
    static void Main()
    {
            // Create a new request to the mentioned URL.
            WebRequest myWebRequest= WebRequest.Create("http://www.contoso.com");

            // Create an instance of the RequestState and assign 
            // 'myWebRequest' to it's request field.
            RequestState myRequestState = new RequestState();
            myRequestState.request = myWebRequest;
            myWebRequest.ContentType="application/x-www-form-urlencoded";

            // Set the 'Method' property to 'POST' to post data to a Uri.
            myRequestState.request.Method="POST";
            // Start the Asynchronous 'BeginGetRequestStream' method call.
            IAsyncResult r=(IAsyncResult) myWebRequest.BeginGetRequestStream(
                new AsyncCallback(ReadCallback),myRequestState);
            // Pause the current thread until the async operation completes.
            Console.WriteLine("main thread waiting...");
            allDone.WaitOne();
            // Assign the response object of 'WebRequest' to a 'WebResponse' variable.
            WebResponse myWebResponse = myWebRequest.GetResponse();
            Console.WriteLine("The string has been posted.");
            Console.WriteLine("Please wait for the response...");

            Stream streamResponse = myWebResponse.GetResponseStream();
            StreamReader streamRead = new StreamReader( streamResponse );
            Char[] readBuff = new Char[256];
            int count = streamRead.Read( readBuff, 0, 256 );
            Console.WriteLine("\nThe contents of the HTML page are ");

            while (count > 0) 
            {
                String outputData = new String(readBuff, 0, count);
                Console.Write(outputData);
                count = streamRead.Read(readBuff, 0, 256);
            }

            // Close the Stream Object.
            streamResponse.Close();
            streamRead.Close();

            // Release the HttpWebResponse Resource.
            myWebResponse.Close();
    }
    private static void ReadCallback(IAsyncResult asynchronousResult)
    {
            RequestState myRequestState =(RequestState) asynchronousResult.AsyncState;
            WebRequest myWebRequest = myRequestState.request;

            // End the Asynchronous request.
            Stream streamResponse = myWebRequest.EndGetRequestStream(asynchronousResult);

            // Create a string that is to be posted to the uri.
            Console.WriteLine("Please enter a string to be posted:");
            string postData = Console.ReadLine();
            // Convert the string into a byte array.
            byte[] byteArray = Encoding.UTF8.GetBytes(postData);

            // Write the data to the stream.
            streamResponse.Write(byteArray,0,postData.Length);
            streamResponse.Close();
            allDone.Set();
    }
}
Imports System.Net
Imports System.IO
Imports System.Text
Imports System.Threading

Public Class RequestState
    ' This class stores the request state of the request.
    Public request As WebRequest
    
    Public Sub New()
        request = Nothing
    End Sub
End Class


Class WebRequest_BeginGetRequeststream
    Public Shared allDone As New ManualResetEvent(False)
    
    Shared Sub Main()
          ' Create a new request.
            Dim myWebRequest As WebRequest = WebRequest.Create("http://www.contoso.com/codesnippets/next.asp")
 ' Create an instance of the RequestState and assign 
            ' myWebRequest' to it's request field.
            Dim myRequestState As New RequestState()
            myRequestState.request = myWebRequest
            myWebRequest.ContentType = "application/x-www-form-urlencoded"

            ' Set the 'Method' property  to 'POST' to post data to a Uri.
            myRequestState.request.Method = "POST"
            ' Start the asynchronous 'BeginGetRequestStream' method call.
            Dim r As IAsyncResult = CType(myWebRequest.BeginGetRequestStream(AddressOf ReadCallback, myRequestState), IAsyncResult)
            ' Pause the current thread until the async operation completes.
            allDone.WaitOne()
            ' Send the Post and get the response.
            Dim myWebResponse As WebResponse = myWebRequest.GetResponse()
            Console.WriteLine(ControlChars.Cr + "The string has been posted.")
            Console.WriteLine("Please wait for the response....")
            Dim streamResponse As Stream = myWebResponse.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 the HTML page are ")
            While count > 0
                Dim outputData As New [String](readBuff, 0, count)
                Console.WriteLine(outputData)
                count = streamRead.Read(readBuff, 0, 256)
            End While

           ' Close the Stream Object.
            streamResponse.Close()
            streamRead.Close()
            ' Release the HttpWebResponse Resource.
             myWebResponse.Close()
    End Sub
     
    Private Shared Sub ReadCallback(asynchronousResult As IAsyncResult)
            Dim myRequestState As RequestState = CType(asynchronousResult.AsyncState, RequestState)
            Dim myWebRequest As WebRequest = myRequestState.request
            ' End the request.
            Dim streamResponse As Stream = myWebRequest.EndGetRequestStream(asynchronousResult)
            ' Create a string that is to be posted to the uri.
            Console.WriteLine(ControlChars.Cr + "Please enter a string to be posted:")
            Dim postData As String = Console.ReadLine()
            Dim encoder As New ASCIIEncoding()
            ' Convert  the string into a byte array.
            Dim byteArray As Byte() = Encoding.UTF8.GetBytes(postData)
            ' Write the data to the stream.
            streamResponse.Write(byteArray, 0, postData.Length)
            streamResponse.Close()
            ' Allow the main thread to resume.
            allDone.Set()
    End Sub
End Class

Remarks

Caution

WebRequest, HttpWebRequest, ServicePoint, and WebClient are obsolete, and you shouldn't use them for new development. Use HttpClient instead.

When overridden in a descendant class, the Method property contains the request method to use in this request.

Note

The WebRequest class is an abstract class. The actual behavior of WebRequest instances at run time is determined by the descendant class returned by the WebRequest.Create method. For more information about default values and exceptions, see the documentation for the descendant classes, such as HttpWebRequest and FileWebRequest.

Notes to Implementers

The Method property can contain any valid request method for the protocol implemented. The default value must provide a default request/response transaction that does not require protocol-specific properties to be set.

Applies to

See also