Why Re-throw Exceptions?

Question

I\'ve seen the following code many times:

try
{
    ... // some code
}
catch (Exception ex)
{
    ... // Do something
    throw new CustomException(ex);

            


        

Answer 1

FYI, this is a related question about each type of re-throw: Performance Considerations for throwing Exceptions

My question focuses on "Why" we re-throw exceptions and its usage in application exception handling strategy.