c# windows form 生命周期 (Life cycle) 事件 顺序 窗口 初始化
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微软官方的文档：
form 打开:
• Control.HandleCreated
• Control.BindingContextChanged
• Form.Load
• Control.VisibleChanged
• Form.Activated
• Form.Shown
from 关闭：
• Form.Closing
• Form.FormClosing
• Form.Closed
• Form.FormClosed
• Form.Deactivate
control ,change focus:(使用 tab ,shift + tab等等，或是调用Select,SelectNextControl，或是使用当前form的ActiveControl)
• Enter
• GotFocus
• Leave
• Validating
• Validated
• LostFocus
control ,change focus:(使用鼠标，或是通过调用Focus方法)
• Enter
• GotFocus
• LostFocus
• Leave
• Validating
• Validated
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Move,Load,VisibleChanged 以及 Activated 事件在form显示之前就触发了。
事件的含义：
- Move: This event occurs when the form is moved. Although by default, when a form is instantiated and launched, the user does not move it, yet this event is triggered before the Load event occurs.
- Load: This event occurs before a form is displayed for the first time.
- VisibleChanged: This event occurs when the Visible property value changes.
- Activated: This event occurs when the form is activated in code or by the user.
- Shown: This event occurs whenever the form is first displayed.
- Paint: This event occurs when the control is redrawn.
- Deactivate: This event occurs when the form loses focus and is not the active form.
- Closing: This event occurs when the form is closing.
- Closed: This event occurs when the form is being closed.
Explain the key events in the lifecycle of the form.
a. Load: fired when form is first loaded in the application
b. Activated: fired whenever the form gets the focus i.e. when loaded first time, restored from the minimize state, whenever the form is brought in front.
c. Deactivated: fired whenever the form looses focus i.e. when form is closed, minimized, when it is in background.
d. Closing: Triggered when application wishes to be closed.
e. Closed: Triggered when application is closed.
f. Disposed: Used for garbage collection.
事件的顺序：
Form Events:
- Construtor
- Load
- Layout
- Activated
- Paint
- Closing
- Closed
- Deactivate
- Dispose
and for Controls:
- Enter
- GotFocus
- Leave
- Validating
- Validated
- LostFocus
另一个版本的form event 顺序
Load
VisibleChanged
Activated
Shown
Paint
Deactivate
Activated
Paint
Formclosing
FormClosed
Deactivate
Form Startup
- OnHandleCreated
- OnCreateControl
- OnLoad
- OnActivated
- OnShown
Form Shutdown
- OnClosing
- OnClosed
- OnDeactivate
- OnHandleDestroyed
