I'm learning about ASP.NET, mainly by following through a book, but also making an effort to actually do things along the way. But, I came across an explanation about list controls which I don't understand. This is what it says:
the last option sets the AutoPostBack property of the control. With this option checked, the control will submit the page it's contained in back to the server as soon as the user chooses a new item from the list
Can you explain this statement for me?
For normal client controls (such as a list control with AutoPostBack set to false), when a user chooses an item in the list, the browser does not communicate with the server. There's no network traffic and no delay for your user before they see the results of the choice, but there's also no opportunity to do anything in your server code, like calculate dependent values. If you want to do anything to the screen in response to the choice, you have to use a client-side script.
When AutoPostBack is set to true, selecting an item in the list sends a message to the server (via an HTTP POST). ASP.NET then executes whatever code you have attached to the list's changed event, rebuilds the page, and sends the revised page to the client.