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 setting of its NamingContainer control.|
|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 (_).|
|The ClientID value is set to the value of the ID property. If the control is a naming container, the control is used as the top of the hierarchy of naming containers for any controls that it contains.|
You use the enumeration when you set 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.
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.)
For more information, see ASP.NET Web Server Control Identification.
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 Identification
<asp:XmlDataSource ID="XmlDataSource1" runat="server" XPath="Products/Product"> <Data> <Products> <Product ProductID="1" ProductName="Chai" /> <Product ProductID="34" ProductName="Ale" /> <Product ProductID="43" ProductName="Coffee" /> </Products> </Data> </asp:XmlDataSource> <asp:ListView ID="ListView1" ClientIDMode="Predictable" ClientIDRowSuffix="ProductID" DataSourceID="XmlDataSource1" runat="server" > <ItemTemplate> ProductID: <asp:Label ID="ProductIDLabel" runat="server" Text='<%# Eval("ProductID") %>' /> <br /> ProductName: <asp:Label ID="ProductNameLabel" runat="server" Text='<%# Eval("ProductName") %>' /> <br /> <br /> </ItemTemplate> <LayoutTemplate> <div ID="itemPlaceholderContainer" runat="server"> <span ID="itemPlaceholder" runat="server" /> </div> <div> </div> </LayoutTemplate> </asp:ListView>