Flash Remoting: The Definitive Guide

Error Handling in Flash Remoting with .NET

One of the true marks of a good programmer is how she handles errors in the code. Programmers coming from a Classic ASP background likely have very brief experience with good error handling. Flash taps directly into .NET’s robust error-handling mechanisms. This section discusses how to trap errors and expose them to your Flash application. We also discuss different error-handling techniques and how to use them with Flash. For related information, see Section 6.5.

Catch Me If You Can

The .NET languages support the try/catch construct for error handling. When an error occurs, code execution stops and the .NET Framework raises an exception. The following C# snippet includes code that may raise an exception, depending on the value of divisor:

int divideIt (int numerator, int divisor) {
  return = numerator / divisor;
}

This code will raise a DivideByZeroException if divisor is 0, because dividing by zero is a mathematical impossibility. Though you can avoid the exception by checking the divisor for a zero value before performing the division, there are situations where anticipating an exception is difficult if not impossible. For example, if you write code that connects to a remote SQL Server and the remote server reboots while your code is running, you’re going to find yourself with a big fat exception.

Luckily, handling exceptions is easy. You can handle the DivideByZeroException by adding a try /catch block, as follows. If the exception is raised ...