Provides methods for encoding and decoding URLs when processing Web requests. This class cannot be inherited.
Namespace: System.Web
Assembly: System.Web (in system.web.dll)
Visual Basic (Declaration)
Public NotInheritable Class HttpUtility
Dim instance As HttpUtility
public sealed class HttpUtility
public ref class HttpUtility sealed
public final class HttpUtility
public final class HttpUtility
The HttpUtility class is used internally by the HttpServerUtility class, whose methods and properties are exposed through the intrinsic ASP.NET Server object. Additionally, the HttpUtility class contains encoding and decoding utility methods that are not accessible from the Server.
The following code example demonstrates the use of the HtmlEncode, HtmlDecode, and ParseQueryString methods of the HttpUtility class.
<%@ Page Language="VB" %>
<script runat="server">
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
Dim currurl As String = HttpContext.Current.Request.RawUrl
Dim querystring As String = Nothing
' Check to make sure some query string variables
' exist and if not add some and redirect.
Dim iqs As Int32 = currurl.IndexOf("?".ToCharArray())
If (iqs = -1) Then
Dim redirecturl As String = currurl & "?var1=1&var2=2+2%2f3&var1=3"
Response.Redirect(redirecturl, True)
' If query string variables exist, put them in
' a string.
ElseIf (iqs >= 0) Then
If (iqs < currurl.Length - 1) Then
querystring = currurl.Substring(iqs + 1)
End If
End If
' Parse the query string variables into a NameValueCollection.
Dim qscoll As NameValueCollection = HttpUtility.ParseQueryString(querystring)
' Iterate through the collection.
Dim sb As New StringBuilder()
For Each s As String In qscoll.AllKeys
sb.Append(s & " - " & qscoll(s) & "<br>")
Next s
' Write the results to the appropriate labels.
ParseOutput.Text = sb.ToString()
UrlRawOutput.Text = currurl
UrlEncodedOutput.Text = HttpUtility.UrlEncode(currurl)
UrlDecodedOutput.Text = HttpUtility.UrlDecode(currurl)
End Sub
</script>
<html>
<head id="Head1" runat="server">
<title>HttpUtility ParseQueryString Example</title>
</head>
<body>
<form id="Form1" runat="server">
The raw url is: <br />
<asp:Label id="UrlRawOutput"
runat="server" />
<br /><br />
The url encoded is: <br />
<asp:Label id="UrlEncodedOutput"
runat="server" />
<br /><br />
The url decoded is: <br />
<asp:Label id="UrlDecodedOutput"
runat="server" />
<br /><br />
The query string NameValueCollection is: <br />
<asp:Label id="ParseOutput"
runat="server" />
</form>
</body>
</html>
<%@ Page Language="C#"%>
<script runat="server">
protected void Page_Load(object sender, EventArgs e)
{
String currurl = HttpContext.Current.Request.RawUrl;
String querystring = null ;
// Check to make sure some query string variables
// exist and if not add some and redirect.
int iqs = currurl.IndexOf('?');
if (iqs == -1)
{
String redirecturl = currurl + "?var1=1&var2=2+2%2f3&var1=3";
Response.Redirect(redirecturl, true);
}
// If query string variables exist, put them in
// a string.
else if (iqs >= 0)
{
querystring = (iqs < currurl.Length - 1) ? currurl.Substring(iqs + 1) : String.Empty;
}
// Parse the query string variables into a NameValueCollection.
NameValueCollection qscoll = HttpUtility.ParseQueryString(querystring);
// Iterate through the collection.
StringBuilder sb = new StringBuilder();
foreach (String s in qscoll.AllKeys)
{
sb.Append(s + " - " + qscoll[s] + "<br>");
}
// Write the results to the appropriate labels.
ParseOutput.Text = sb.ToString();
UrlRawOutput.Text = currurl;
UrlEncodedOutput.Text = HttpUtility.UrlEncode(currurl);
UrlDecodedOutput.Text = HttpUtility.UrlDecode(currurl);
}
</script>
<html>
<head runat="server">
<title>HttpUtility ParseQueryString Example</title>
</head>
<body>
<form runat="server">
The raw url is: <br />
<asp:Label id="UrlRawOutput"
runat="server" />
<br /><br />
The url encoded is: <br />
<asp:Label id="UrlEncodedOutput"
runat="server" />
<br /><br />
The url decoded is: <br />
<asp:Label id="UrlDecodedOutput"
runat="server" />
<br /><br />
The query string NameValueCollection is: <br />
<asp:Label id="ParseOutput"
runat="server" />
</form>
</body>
</html>
System.Object
System.Web.HttpUtility
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Windows 98, Windows 2000 SP4, 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