Control.FindControl Method (String)
Searches the current naming container for a server control with the specified id parameter.
Assembly: System.Web (in System.Web.dll)
'Declaration Public Overridable Function FindControl ( _ id As String _ ) As Control 'Usage Dim instance As Control Dim id As String Dim returnValue As Control returnValue = instance.FindControl(id)
Parameters
- id
- Type: System.String
The identifier for the control to be found.
Return Value
Type: System.Web.UI.ControlThe specified control, or Nothing if the specified control does not exist.
Use FindControl to access a control from a function in a page's code, to access a control that is inside another container, or in other circumstances where the target control is not directly accessible to the caller. This method will find a control only if the control is directly contained by the specified container; that is, the method does not recursively search through a hierarchy of controls within controls. For information about how to find a control when you do not know its immediate container, see How to: Locate Controls by ID in an ASP.NET Web Page.
| Topic | Location |
|---|---|
| How to: Reference ASP.NET Master Page Content | Building ASP .NET Web Applications |
| How to: Reference ASP.NET Master Page Content | Building ASP .NET Web Applications |
| How to: Reference ASP.NET Master Page Content |
The following example defines a Button1_Click event handler. When invoked, this handler uses the FindControl method to locate a control with an ID property of TextBox2 on the containing page. If the control is found, its parent is determined using the Parent property and the parent control's ID is written to the page. If TextBox2 is not found, "Control Not Found" is written to the page.
Security Note: |
|---|
This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview. |
Private Sub Button1_Click(sender As Object, MyEventArgs As EventArgs) ' Find control on page. Dim myControl1 As Control = FindControl("TextBox2") If (Not myControl1 Is Nothing) ' Get control's parent. Dim myControl2 As Control = myControl1.Parent Response.Write("Parent of the text box is : " & myControl2.ID) Else Response.Write("Control not found.....") End If End Sub
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Security Note: