Specifies how ASP.NET generates the ClientID for a control that can be accessed in client script.
Assembly: System.Web (in System.Web.dll)
The ClientID value is generated by concatenating the ID values of each parent naming container with the ID value of the control. In data-binding scenarios where multiple instances of a control are rendered, an incrementing value is inserted in front of the control's ID value. Each segment is separated by an underscore character (_). This algorithm is the only one that was available in versions of ASP.NET earlier than ASP.NET 4.
The control inherits the NamingContainer control.setting of its
This algorithm is used for controls that are in data-bound controls. The ClientID value is generated by concatenating the ClientID value of the parent naming container with the ID value of the control. If the control is a data-bound control that generates multiple rows, the value of the data field specified in the ClientIDRowSuffix property is added at the end. For the GridView control, multiple data fields can be specified. If the ClientIDRowSuffix property is blank, a sequential number is added at the end instead of a data field value. Each segment is separated by an underscore character (_).
You use the ClientIDMode property for a control. The value that you assign to the ClientIDMode property determines how the ClientID property is generated. The value of the ClientID property is rendered as the id attribute in markup, and it is the value that you use to access the control from client script. The value that you assign to the ClientIDMode property does not affect the ID property of the server control, only the id attribute of the corresponding HTML element.enumeration when you set the
Because the default for controls is, the default generation mode is . (However, if you use Visual Studio to convert a Web project to ASP.NET 4 from an earlier version, Visual Studio automatically sets the site default to in the Web.config file.)
You can set the ClientIDMode value for all pages in a Web site by setting the element in the site's Web.config file. You can set the ClientIDMode value for a page in the directive.
For more information, see ASP.NET Web Server Control Identification.
Legacy Code Example
The following example shows Label controls that are contained in a ListView control. On the ListView control, the ClientIDMode property is set to and the ClientIDRowSuffix property is set to ProductID. From client script, you can access a particular instance of a Label based on the ProductID value of the instance that you are trying to access.
This example creates HTML with three ProductIDLabel controls. When the page runs, the IDs for the controls will be the following:
For more information, see ASP.NET Web Server Control IdentificationCode snippet is not found. Confirm that the code snippet name 'System.Web.UI.ClientIDMode' is correct.
Available since 4.0
ASP.NET Web Server Control Identification