这是一个判断闰年的小程序，只要你随意输入一个年份，程序就会自动帮你算出是不是闰年，并显示结果给你看！-This is a small leap year judgment procedures, as long as you can input a year, procedures will automatically help you calculate it is not a leap year, and the result will be displayed for you!

有两个DateTimePicker控件，可以选择起始和终止年份，最终结果以弹窗形式显示， 里面有自己创建类的代码 ，计算闰年个数-There are two DateTimePicker control, you can select the start and end the year, the final results are displayed in pop, which has its own code to create a class, calculate the number

简单的小程序，判断是否是闰年，初学者学习-Determine whether it is a leap year