C# lets you create your own exception classes for specific error types.
🛠️ Defining a Custom Exception
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| class NegativeNumberException : Exception
{
public NegativeNumberException(string message) : base(message) { }
}
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🏷️ Using Your Exception
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| void AcceptOnlyPositive(int n)
{
if (n < 0)
throw new NegativeNumberException("Number must be positive.");
}
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🛡️ Catching Your Exception
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| try
{
AcceptOnlyPositive(-5);
}
catch (NegativeNumberException ex)
{
Console.WriteLine(ex.Message); // "Number must be positive."
}
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💡 When to Create Custom Exceptions
- When you want to signal a specific error in your app.
- When you need to distinguish your errors from others.
Next: Exception best practices!
