The throw statement is used to signal the occurrence of an anomalous situation (exception) during the program execution. The throw statement takes the form:
throw [expression];
where:
The thrown exception is an object whose class is derived from System.Exception, for example:
class MyException : System.Exception {} throw new MyException();
Usually the throw statement is used with try-catch or try-finally statements. When an exception is thrown, the program looks for the catch statement that handles this exception.
This example demonstrates how to throw an exception using the throw statement.
// throw example using System; public class ThrowTest { public static void Main() { string s = null; if (s == null) { throw(new ArgumentNullException()); } Console.Write("The string s is null"); // not executed } }
Caught exception: System.ArgumentNullException: argument can't be null at ThrowTest.Main()
See the try-catch, try-finally and try-catch-finally examples.
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