HtmlInputHidden Class
Assembly: System.Web (in system.web.dll)
'Declaration Public Class HtmlInputHidden Inherits HtmlInputControl Implements IPostBackDataHandler 'Usage Dim instance As HtmlInputHidden
public class HtmlInputHidden extends HtmlInputControl implements IPostBackDataHandler
public class HtmlInputHidden extends HtmlInputControl implements IPostBackDataHandler
You can use the HtmlInputHidden control to embed information that is hidden from the user within a <form> element. This information is sent when the Web page is posted back to the server. The HtmlInputHidden control provides a ServerChange event that is raised when the Value property changes values between posts to the server. This allows you to create an event handler that performs a custom set of instructions each time the event is raised.
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| The HtmlInputHidden control does not provide a built-in way to post back to the server. You must provide another control on the Web page that supports posting to the server, such as an HtmlButton control, to send the value of the control back to the server. |
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| The ASP.NET page framework uses this HTML feature to automatically load and persist the view state of server controls on a page. |
For a list of initial property values for an instance of HtmlInputHidden, see the HtmlInputHidden constructor.
| Topic | Location |
|---|---|
| How to: Add HTML Server Controls to a Web Page Using ASP.NET Syntax | Building ASP .NET Web Applications |
| How to: Set HTML Server Control Properties Programmatically | Building ASP .NET Web Applications |
| How to: Add HTML Server Controls to a Web Page Using ASP.NET Syntax | Building ASP .NET Web Applications |
| How to: Set HTML Server Control Properties Programmatically | Building ASP .NET Web Applications |
The following code example demonstrates how to use an HtmlInputHidden control to store information on the Web page between posts to the server.
<%@ Page Language="VB" AutoEventWireup="True" %> <html> <head> <script language="VB" runat="server"> Sub Page_Load(sender As Object, e As EventArgs) If Page.IsPostBack Then Span1.InnerHtml = "Hidden value: " & "<b>" & HiddenValue.Value & "</b>" End If End Sub 'Page_Load Sub SubmitBtn_Click(sender As Object, e As EventArgs) HiddenValue.Value = StringContents.Value End Sub 'SubmitBtn_Click </script> </head> <body> <form runat=server> <h3>HtmlInputHidden Sample</h3> <input id="HiddenValue" type=hidden value="Initial Value" runat=server> Enter a string: <input id="StringContents" type=text size=40 runat=server> <p> <input type=submit value="Enter" OnServerClick="SubmitBtn_Click" runat=server> <p> <span id=Span1 runat=server> This label will display the previously entered string. </span> </form> </body> </html>
- AspNetHostingPermission for operating in a hosted environment. Demand value: LinkDemand; Permission value: Minimal.
- AspNetHostingPermission for operating in a hosted environment. Demand value: InheritanceDemand; Permission value: Minimal.
System.Web.UI.Control
System.Web.UI.HtmlControls.HtmlControl
System.Web.UI.HtmlControls.HtmlInputControl
System.Web.UI.HtmlControls.HtmlInputHidden
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.
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