.NET Framework Class Library
WebClient Constructor

Initializes a new instance of the WebClient class.

Namespace:  System.Net
Assembly:  System (in System.dll)
Syntax

Visual Basic (Declaration)
Public Sub New
Visual Basic (Usage)
Dim instance As New WebClient()
C#
public WebClient()
Visual C++
public:
WebClient()
JScript
public function WebClient()
Remarks

The default constructor creates a new instance of the WebClient class. The default HTTP method is GET. The default FTP method is RETR. The default Encoding is Default. The default value of AllowAutoRedirect is true.

Examples

The following code example creates a WebClient instance and then uses it to download data from a server and display it on the system console, to download data from a server and write it to a file, and to upload form values to a server and receive the response.

Visual Basic
    Public Shared Sub Main()


        Try
            Dim client As New WebClient()
            Dim pageData As [Byte]() = client.DownloadData("http://www.contoso.com")
            Dim pageHtml As String = Encoding.ASCII.GetString(pageData)

            ' Download the data to a buffer.
            Console.WriteLine(pageHtml)

            ' Download the data to a file.
            client.DownloadFile("http://www.contoso.com", "page.htm")


            ' Upload some form post values.
            dim form as New NameValueCollection()
               form.Add("MyName", "MyValue")  

               ' Note that you need to replace "http://localhost/somefile.aspx" with the name of 
               ' a file that is available to your computer.
               Dim responseData As [Byte]() = client.UploadValues("http://www.contoso.com/form.aspx", form)      
            Console.WriteLine(Encoding.ASCII.GetString(responseData))

        Catch webEx As WebException
            if webEx.Status = WebExceptionStatus.ConnectFailure then
               Console.WriteLine("Are you behind a firewall?  If so, go through the proxy server.")
            end if
            Console.Write(webEx.ToString())
        End Try


    End Sub 'Main
C#
        try {
            
        // Download the data to a buffer.
               WebClient client = new WebClient();

          Byte[] pageData = client.DownloadData("http://www.contoso.com");
        string pageHtml = Encoding.ASCII.GetString(pageData);
        Console.WriteLine(pageHtml);

        // Download the data to a file.
                client.DownloadFile("http://www.contoso.com", "page.htm");

        // Upload some form post values.
        NameValueCollection form = new NameValueCollection();        
        form.Add("MyName", "MyValue");        
        Byte[] responseData = client.UploadValues("http://www.contoso.com/form.aspx", form);        

        }
        catch (WebException webEx) {
              Console.WriteLine(webEx.ToString());
               if(webEx.Status == WebExceptionStatus.ConnectFailure) {
                   Console.WriteLine("Are you behind a firewall?  If so, go through the proxy server.");
               }
        }
Visual C++
try
{
   // Download the data to a buffer.
   WebClient^ client = gcnew WebClient;

   array<Byte>^ pageData = client->DownloadData( "http://www.contoso.com" );
   String^ pageHtml = Encoding::ASCII->GetString( pageData );
   Console::WriteLine( pageHtml );

   // Download the data to a file.
   client->DownloadFile( "http://www.contoso.com", "page.htm" );

   // Upload some form post values.
   NameValueCollection^ form = gcnew NameValueCollection;
   form->Add( "MyName", "MyValue" );
   array<Byte>^ responseData = client->UploadValues( "http://www.contoso.com/form.aspx", form );
}
catch ( WebException^ webEx ) 
{
   Console::WriteLine( webEx->ToString() );
   if ( webEx->Status == WebExceptionStatus::ConnectFailure )
   {
      Console::WriteLine( "Are you behind a firewall?  If so, go through the proxy server." );
   }
}
CPP_OLD
try {

    // Download the data to a buffer.
    WebClient* client = new WebClient();

    Byte pageData[] = client->DownloadData(S"http://www.contoso.com");
    String* pageHtml = Encoding::ASCII->GetString(pageData);
    Console::WriteLine(pageHtml);

    // Download the data to a file.
    client->DownloadFile(S"http://www.contoso.com", S"page.htm");

    // Upload some form post values.
    NameValueCollection* form = new NameValueCollection();        
    form->Add(S"MyName", S"MyValue");        
    Byte responseData[] = client->UploadValues(S"http://www.contoso.com/form.aspx", form);        

}
catch (WebException* webEx) {
    Console::WriteLine(webEx->ToString());
    if(webEx->Status == WebExceptionStatus::ConnectFailure) {
        Console::WriteLine(S"Are you behind a firewall?  If so, go through the proxy server.");
    }
}
Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Version Information

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0
See Also

Reference

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