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说明：  新建一个应用程序，并添加两个Label控件，三个Edit控件，四个Button按钮。其中两个edit输入框用于输入整数，一个Edit输入框用于输出结果；Label标签控件用于显示当前所做的运算（例如：当单击加法按钮时即做加法运算，则label标签显示”+”号。）；四个Button按钮分别完成加、减、乘、除运算。 编写程序，输入两个整数，顺序执行两个数的加、减、乘、除计算结果并输出。 (Create a new application, and add two Label controls, three Edit controls, four Button button. Two of them used to edit input box enter an integer, an input box for Edit output Label label control used to display the current operation done (for example: When you click that button to do adder addition operations, the labels show label " + " sign.) four Button button respectively add, subtract, multiply, with the exception of computing. Programming, enter the two integers, the order of the implementation of both the number of add, subtract, multiply, with the exception of the calculation results and output.)