The user-input
methods provide a certain amount of inherent error trapping in that
they require the user to enter a certain type of data. If the user
tries to enter some other data, AutoCAD rejects the input and
reprompts the user. Using the InitializeUserInput method with the
user input functions provides additional control of the user input
but can also introduce additional conditions that must be verified
through error trapping. For an example of error trapping that is
required with certain types of user-input, see
Prompt for User Input.