You can use the javascript event window.onUnload

>How would i know if the window is closing?
>
>TIA
>
>>Hi Larry,
>>
>>Use the following javascript from the opened window while closing:
>>
>>

>>window.opener.location.reload();
>>

>>
>>
>>>Hi,
>>>
>>>i mean how to refresh the page1.aspx after closing the Page2.aspx which i call from page1.aspx?
>>>
>>>
>>>TIA
>>>
>>>>Hi Larry,
>>>>
>>>>This process sounds okay, except you would 'window.open("page2.aspx")' instead of page1.
>>>>
>>>>>Hi,
>>>>>
>>>>>How about this process...
>>>>>
>>>>>page1.aspx has datagrid and button and when the user click the button of page1.aspx i want to window.open("page1.aspx") then after closing the page2.aspx i want to refresh the datagrid from page1.aspx automatically just to see my entry in page2.aspx. (NOTE: I used session("myDS") as my container of table or temporary table or dataset).
>>>>>
>>>>>TIA
>>>>>
>>>>>
>>>>>>From inside of Page 2 you could use your code below. Make sure your DataSet is small. You don't want to use up too many resources.
>>>>>>
>>>>>>>Hi,
>>>>>>>
>>>>>>>how about session("myDS") = Page2.Dataset
>>>>>>>
>>>>>>>TIA
>>>>>>>
>>>>>>>>Hi Larry,
>>>>>>>>
>>>>>>>>You can pass the information two different ways in ASP.NET.
>>>>>>>>
>>>>>>>>First you can use the Session object to pass the info. In Page2 you would save the info into a Session variable. In Page 1 you would use the session variable.
>>>>>>>>
>>>>>>>>in Page 2:
>>>>>>>>

>>>>>>>>Session["MyString"] = "my string contents";
>>>>>>>>

>>>>>>>>
>>>>>>>>in Page 1:
>>>>>>>>

>>>>>>>>string YourString = Session["MyString"];
>>>>>>>>if (Session["MyString"] != null)
>>>>>>>>{
>>>>>>>>	string Page2str = (string)Session["MyString"];
>>>>>>>>	// code to process the value of the string here
>>>>>>>>}
>>>>>>>>

>>>>>>>>
>>>>>>>>
>>>>>>>>The other approach is to use a querystring when calling Page 1 from Page 2. This can only be done when the string would always be less than 255 characters.
>>>>>>>>
>>>>>>>>in Page 2:
>>>>>>>>

>>>>>>>>//set the URL string to call for Page 1
>>>>>>>>string Page1url = "Page1.aspx?mystring=" + "your string contents";
>>>>>>>>

>>>>>>>>
>>>>>>>>in Page 1:
>>>>>>>>

>>>>>>>>string Page2str = Request.QueryString(["mystring"]);
>>>>>>>>

>>>>>>>>
>>>>>>>>
>>>>>>>>>Hi,
>>>>>>>>>
>>>>>>>>>ff:
>>>>>>>>>
>>>>>>>>>Page1.aspx --> is my main PAGE
>>>>>>>>>
>>>>>>>>>Page2.aspx --> the popup web form...
>>>>>>>>> --> has a public property of STRNAME AS STRING
>>>>>>>>>
>>>>>>>>>i want to retrieve the value of Page2.aspx from Page2.aspx after the window close of Page2.aspx..
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>TIA