将之前导入Excel和txt数据的代码(具体地址见：http://www.pudn.com/downloads385/sourcecode/windows/database/detail1653649.html)封装为dll，利用回调函数可以获得通过dll传回的数据-compile the previous file input program(http://www.pudn.com/downloads385/sourcecode/windows/database/detail1653649.h