error

Unable to cast object of type 'System.Web.UI.WebControls.ContentPlaceHolder' to type 'System.Web.UI.WebControls.GridViewRow'.

Description:An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.InvalidCastException: Unable to cast object of type 'System.Web.UI.WebControls.ContentPlaceHolder' to type 'System.Web.UI.WebControls.GridViewRow'.

Source Error:

Line 364:        DataTable dt = new DataTable();
Line 365:        DropDownList L112 = (DropDownList)sender;Line 366: GridViewRow row = (GridViewRow)L112.NamingContainer; Line 367:        DropDownList L2 = (DropDownList)row.FindControl("DropDownList1");
Line 368:        DropDownList L3 = (DropDownList)row.FindControl("DropDownList2");