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WebClient Constructor

Initializes a new instance of the WebClient class.

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

'Declaration
Public Sub New
'Usage
Dim instance As New WebClient
public WebClient ()
public function 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()


    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

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

    ubyte pageData[] = client.DownloadData("http://www.contoso.com");
    String pageHtml = Encoding.get_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");
    ubyte responseData[] = client.UploadValues(
        "http://www.contoso.com/form.aspx", form);
}
catch (WebException webEx) {
    Console.WriteLine(webEx.ToString());
    if (webEx.get_Status().Equals(WebExceptionStatus.ConnectFailure)) {
        Console.WriteLine("Are you behind a firewall?  If so, go" 
            + " through the proxy server.");
    }
}

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

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0, 1.1, 1.0

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