说明：  使用c#编写的一个windows下的grep程序，提供一个简单界面。
(Traditionally grep stands for "Global Regular Expression Print". Global means that an entire file is searched. Regular Expression means that a regular expression string is used to establish a search pattern. Print means that the findings will be displayed. Simply put, grep searches an entire file for the pattern you want and displays its findings. Now two variants of the C# Grep Application are provided: the Windows Form variant and the Console variant. )