HttpServerUtility.UrlEncode Method (String)

 

URL-encodes a string and returns the encoded string.

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

Public Function UrlEncode (
	s As String
) As String

Parameters

s
Type: System.String

The text to URL-encode.

Return Value

Type: System.String

The URL-encoded text.

URL encoding ensures that all browsers will correctly transmit text in URL strings. Characters such as a question mark (?), ampersand (&), slash mark (/), and spaces might be truncated or corrupted by some browsers. As a result, these characters must be encoded in <a> tags or in query strings where the strings can be re-sent by a browser in a request string.

This method is a convenient way to access the HttpUtility.UrlEncode method at run time from an ASP.NET application. Internally, this method uses HttpUtility.UrlEncode to encode strings.

In the code-behind file for an ASP.NET web page, access an instance of the HttpServerUtility class through the Server property. In a class that is not in a code-behind file, use HttpContext.Current.Server to access an instance of the HttpServerUtility class.

Outside of a web application, use the WebUtility class to encode or decode values.

The following example shows how to URL-encode a value that is used as a query string value of a hyperlink. The code resides in the code-behind file for a web page. The value to encode is hard-coded in this example only to simplify the example and show the type of value you might URL-encode. Typically, you would URL-encode a value that you received from the user or the request. NextPage refers to a HyperLink control.

Public Class _Default
    Inherits Page

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
        Dim destinationURL = "http://www.contoso.com/default.aspx?user=test"

        NextPage.NavigateUrl = "~/Finish?url=" + Server.UrlEncode(destinationURL)
    End Sub
End Class

The next example is similar to the previous example except it shows how to URL-encode a value from within a class that is not in the code-behind file.

Public Class SampleClass
    Public Function GetUrl() As String
        Dim destinationURL = "http://www.contoso.com/default.aspx?user=test"

        Return "~/Finish?url=" + HttpContext.Current.Server.UrlEncode(destinationURL)
    End Function
End Class

.NET Framework
Available since 1.1
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