The switch command allows you to choose one of several options in your code. It is similar to switch in C, except that it is more flexible, because you can switch on strings, instead of just integers.
The string will be compared to a set of patterns, and when a pattern matches the string, the code associated with that pattern will be evaluated. It's a good idea to use the switch command when you want to match a variable against several possible values, and don't want to do a long series of if......
원문 링크 : Textual Comparison - switch
