Plug_In_1

代码说明：

  这是插件程序中一个插件的实际例子，里面已经给出了很详细的实现。大家看一下，自己子要稍加改造，就可以应用于自己的工程。(This is a plug-in procedures plugin actual examples, which has given a very detailed implementation. We look at their son to a little alteration, it can be applied to their project.)