Sometimes, your code needs to tell the user “something went wrong.” You do this by throwing exceptions.
🏗️ Throwing an Exception
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void Divide(int a, int b)
{
if (b == 0)
throw new ArgumentException("Cannot divide by zero!");
Console.WriteLine(a / b);
}
🧑💻 Why Throw Exceptions?
- To signal that something is wrong and the program should not continue as usual.
- Makes bugs easier to find.
🛡️ Handling Thrown Exceptions
Catch them where it makes sense:
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try
{
Divide(10, 0);
}
catch (ArgumentException ex)
{
Console.WriteLine(ex.Message); // "Cannot divide by zero!"
}
💡 Try It!
Write a method that throws an exception if a string is null or empty:
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void PrintName(string name)
{
if (string.IsNullOrEmpty(name))
throw new ArgumentException("Name cannot be empty.");
Console.WriteLine(name);
}
Next: Custom exception classes!
