Server Error in '/' Application. No parameterless constructor defined for this object

Question

The callstack shows the following:

[MissingMethodException: No parameterless constructor defined for this object.]
System.RuntimeTypeHandle.CreateInstance(Ru         


        

Answer 1

Your custom classes in the action args must have a parameterless constructor in order to use the default model binder. Otherwise, either (1) create a custom model binder or (2) pass primitive types instead of custom classes to the Action.