用C#语言编写的一个十进制小键盘程序，这是windows界面下各个按键的代码-C# language using a decimal keypad, this is all under the windows interface of the code button

本代码是在学习C#过程中的小练习，能统计键盘输入字符数的个数。无错误，能运行。-The code is in the process of learning C# a small practice, performance statistics the number keypad to enter the number of characters. Error-free, able to run.