设计一个简单的Win32程序，该程序窗口内正上方居中显示“Windows API画线程序演示”字样，在程序窗口内任意位置按下鼠标左键并拖动到窗口范围内任意位置，松开鼠标左键即可绘制一条蓝色的直线。- Design a simple Win32 program, the program window is centered above the word　Windows API line drawing program demo . Within the program window arbitrary position press the left mouse button and drag to anywhere within the range of the window and release the left mouse button to draw a blue line.