WebClient.UploadString Method (String, String, String)


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Uploads the specified string to the specified resource, using the specified method.

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

public string UploadString(
	string address,
	string method,
	string data


Type: System.String

The URI of the resource to receive the string. This URI must identify a resource that can accept a request sent with the method method.

Type: System.String

The HTTP method used to send the string to the resource. If null, the default is POST for http and STOR for ftp.

Type: System.String

The string to be uploaded.

Return Value

Type: System.String

A String containing the response sent by the server.

Exception Condition

The address parameter is null.


The data parameter is null.


The URI formed by combining BaseAddress and address is invalid.


There was no response from the server hosting the resource.


method cannot be used to send content.

Before uploading the string, this method converts it to a Byte array using the encoding specified in the Encoding property. This method blocks while the string is transmitted. To send a string and continue executing while waiting for the server's response, use one of the UploadStringAsync methods.

If the BaseAddress property is not an empty string ("") and address does not contain an absolute URI, address must be a relative URI that is combined with BaseAddress to form the absolute URI of the requested data. If the QueryString property is not an empty string, it is appended to address.


This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing in the .NET Framework.

The following code example demonstrates calling this method.

public static void PostString (string address)
    string data = "Time = 12:00am temperature = 50";
    string method = "POST";
    WebClient client = new WebClient ();
    string reply = client.UploadString (address, method, data);

    Console.WriteLine (reply);

.NET Framework
Available since 2.0
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