WebClient Constructor

WebClient Constructor

Initializes a new instance of the WebClient class.

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

Public Sub New
Dim instance As New WebClient()

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.

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.

    Public Shared Sub Main()

            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.

            ' 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)      

        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
        End Try 

    End Sub 'Main
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);

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

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.

.NET Framework

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

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