A message is dynamic text that communicates errors, warnings, or other types of information to users. By using messages instead of static text in your user interface, you can provide contextual assistance to users that supports localization.
Each message has a definition that contains text and references to input parameters. In the following message definition, references to input parameters are in braces. The numbers correspond to the order in which you define the input parameters on the Message form.
The {1} must be later than {2} and at least 30 days before {3}.
When you call a message, you pass a tab-delimited string that starts with the message name and provides run-time values for the input parameters. You can pass literal values or property references to a message.
The following strings are example inputs to the DateRange message above:
DateRange\tstart date\ttoday\tthe end date
"DateRange\tstartdate " + .StartDate + " \tJanuary 1, 2006\ttoday"