在桌面显示Windows窗口。窗口内居中显示“大家好，这是我的第一个Windows API程序！”同时播放背景音乐，并可通过程序改变窗口显示风格为只有标题栏，以及鼠标指针形状为手型。-Windows desktop display window. Window centered　Hello, everyone, this is my first Windows API program!　While playing background music, and through the program to change the window display only the title bar style, and the mouse pointer shape hand type.