When overridden in a derived class, this method contains the code to determine whether the value in the input control is valid.
Assembly: System.Web (in System.Web.dll)
Use the method to determine whether the value in the input control specified by the ControlToValidate property is valid.
This method is used primarily by control developers.
You must implement this method in a derived class to return whether the value in the input control is valid.
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.