Can you describe the order in which events are raised during the Load phase of the ASP.NET page life cycle?
During the Load phase of the ASP.NET page life cycle, events are raised in the following order:
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Page.PreLoad: The PreLoad event is the first event raised during the Load phase. It occurs after the page state has been restored, but before the postback data is processed. This event is typically used for tasks that need to be performed before postback data is handled or before control events are raised.
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Control events: After the PreLoad event, individual control events are raised. These events include events like Button.Click, DropDownList.SelectedIndexChanged, GridView.RowDataBound, etc. These events are triggered by user actions or control-specific interactions.
The order of control events depends on the control hierarchy and the sequence of user interactions. The events of child controls are raised before the events of their parent controls. For example, if a button is clicked inside a GridView row, the GridView.RowCommand event will be raised before the Button.Click event.
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Page.Load: The Load event is raised after the control events have been processed. It is the main event of the Load phase. In this event, you can perform tasks such as accessing control values, performing business logic, or updating control properties. The Load event is commonly used to populate controls with data and customize the page based on the user's input.
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Page.LoadComplete: The LoadComplete event is raised after the Load event and signifies that the page and all its controls have been loaded and their states have been updated. This event is typically used for tasks that need to be performed after the page and controls have been completely loaded, such as finalizing data binding or performing additional processing.
It's important to note that this order applies to the standard ASP.NET Web Forms page life cycle, and variations can occur based on specific scenarios, customizations, or extensions implemented in the application.