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I would like to know where I can find the property ISPOSTBACK, for the webform or any web forms controls.

and what is the difference between ispostback and autopostback?

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ISPOSTBACK is available for web form
 Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'Put user code to initialize the page here
            If Not Page.IsPostBack Then
                 Response.Write("Post back event not occurs here")
                 'This block is executed only on the first  time the web form is loaded
                  Response.Write("Post back event  occurs here")
                  'If any server event occurs like button click ,this block will fire
End Sub

AutoPostBack Property is available for web form controls like checkbox,..
-automatically posts back to the server when clicked.


CheckBox.AutoPostBack =True
Gets or sets a value indicating whether the CheckBox state automatically posts back to the server when clicked.

true to automatically post the state of the CheckBox control to the server when it is clicked; otherwise, false. The default is false.

try this link
ispostback is not a property, rather it is a keyword use to test if the pages is reloaded..

autopostback is a property, if it is set to true then everytime you trigger the postback the page will be reloaded..

ispostback is a boolean keyword.
Hi   el_hey ,

your comment is WRONG.

I you refer in MSDN 2003  ispostback is given as property of Page Class.(System.Web.UI.Page)
Page.IsPostBack Property
Gets a value indicating whether the page is being loaded in response to a client postback, or if it is being loaded and accessed for the first time.
Property Value
true if the page is being loaded in response to a client postback; otherwise, false.


AutoPostBack is built into the form-based server controls, and when enabled, automatically posts the page back to the server whenever the value of the control in question is changed. Because of the additional server requests it causes, it's not something you'll want to enable for all your controls, but for things that affect page display or change choices further down the form, it can be really handy. Not to mention the fact that it will save you a lot of time and headaches over trying to implement something similar on your own. Not that it's really all that complex to do on your own if you're good with javascript, but it's hard to get any simpler then just setting AutoPostBack="True"


jskfanAuthor Commented:
if you right-click on the web form and go to properties, the properties window of the web form doesn't show anything that says IsPostback. This is why I thought it's not a design view property.
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