Fix the following error: The type or namespace name 'MethodInfo' could not be found (are you missing a using directive or an assembly reference?)

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Fix the following error:
The type or namespace name 'MethodInfo' could not be found (are you missing a using directive or an assembly reference?)

Replace:
public override bool IsValidName(ControllerContext controllerContext, string actionName, MethodInfo methodInfo)
With:
public override bool IsValidName(ControllerContext controllerContext, string actionName, System.Reflection.MethodInfo methodInfo)