BUTTON控件

button控件属性表：

Property	Description
AutoEllipsis	Specifies whether to append dots (…) when the text in the button is too long and can't fit the button.
AutoSize	Specifies whether the button will automatically resize to fit its content.
FlatStyle	Determines the style of the button. Popup makes the button flat, and when you hover on the button, the button will pop out. Flat makes the button flat and when you move point your mouse inside the button, the background color of the button changes.
Enabled	If set to false, the button cannot be clicked or receive focus.
Image	An optional image that you can place inside the control.
ImageAlign	The alignment of the image in the button.
Text	The caption inside the button.
Visible	Tells whether the button is visible or not.

事件列表：

Event	Description
Click	Occurs when you click the button.
Enter	Occurs when the control becomes the active control of the form.
Leave	Occurs when the control becomes inactive anymore.
LocationChanged	Occurs when the location of the button is changed.
MouseDown	Occurs when the mouse pointer is in the button and the mouse button is pressed down.
MouseEnter	Occurs when the mouse enters the button.
MouseHover	Occurs when the mouse stays stationary in the button for an amount of time.
MouseUp	Occurs when you pressed the button and you let go of the mouse button.
MouseLeave	Occurs when the mouse pointer leaves the button.

Click作为button的默认事件。我们也可以为 button添加其它事件。建立一个新的窗体，从工具箱拖拽一个button控件到窗体上，把button的name属性设为buttonsample。接着为窗体添加MouseEnter 和 MouseLeave事件。

打开属性窗口，单击“闪电”标识添加事件，如下图：

MouseEnter 事件代码：

private void buttonSample_MouseEnter(object sender, EventArgs e)
{
    buttonSample.Text = "Mouse has entered!";
}

MouseLeave事件代码：

private void buttonSample_MouseLeave(object sender, EventArgs e)
{
    btnSample.Text = "Mouse has left!";
}

运行结果截图如下：