Call this method before calling the ClientScriptManager.RegisterOnSubmitStatement(Type, string, string) method to avoid registering duplicate OnSubmit statements. This is particularly important if the statement requires a large amount of server resources to create.

A statement is uniquely identified by its key and its type. Statements with the same key and type are considered duplicates.

This overload of the erload:System.Web.UI.ClientScriptManager.IsOnSubmitStatementRegistered method calls the overload that takes both a key and a type parameter with the type set as a System.Web.UI.Page object