Catch multiple exception types

With the Try-Catch block you can catch multiple exception types with the same block. This is useful for handling different exception types differently.

If you want to catch SqlExceptions from System.Data.SqlClient and handle these for their own, but still want to catch all other Exceptions as well, you can implement something like this:

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catch (SqlException ex)
{
    // SqlException ex.Number == -2 for catching timeout exceptions
    // see https://stackoverflow.com/questions/29664/how-to-catch-sqlserver-timeout-exceptions
    if (ex.Number == -2)
    {
        // Do something in case of timeouts ...
    }
}
catch (Exception ex)
{
    // Do something in every other exception case ...
}

The more specific upper catch is executed if there is such an exception and the lower catch only get executed if there is no specific exception catch before.

Another example

Here is another example to simply test the behavior:

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public static async Task Main(string[] args)
{
    try
    {
        Console.WriteLine("Trowing an Exception ...");
        throw new SomeException("Some text");
    }
    catch (SomeException someEx)
    {
        Console.WriteLine($"Catching someEx: {someEx.Message}");
    }
    catch (Exception ex)
    {
        Console.WriteLine($"Catching ex: {ex.Message}");
    }
}

public class SomeException : Exception
{
    public SomeException(string message) : base(message)
    {
    }
}