滑鼠左键按下事件是最有可能在控制项中包含类别处理的事件。

The left mouse button down event is the most likely event to have class handling in a control.

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在实际例子中，将显示器顶部的滑块指针稍微向右移动一点(就是将鼠标指针放在它上面，按下鼠标左键拖动，然后释放鼠标左键)。

In the working example, move the slider pointer at the top of the display a bit to the right (that is, grab it with your mouse pointer, drag it over, then release the first button).

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下面是可以帮助您在这样小的设备上进行操作的一个快速提示：即使看不到标题条，按下alt +鼠标左键也可以让您在桌面上拖动屏幕。

Here's a quick hint to help you get around on such a tiny device: holding down Alt + left mouse button will allow you to drag screens around on your desktop, even if you can't see the title bar.

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