What is the callBack handler? Is this done in JavaScript or VB?
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Browse All TopicsI have a ASP.NET 2.0 AJAX page with a number of UpdatePanels. One of these contains an image generated by Manifold GIS Internet Map Server. This "image" is actually through a call to a seperate page that returns binary blob data and is written directly with Response.BinaryWrite. In the process it returns an ID value which I am currently storing in a Session variable.
There is a second update panel for information which uses this ID to query a MySQL database. My problem is that I can't get hold of the Session variable until the image has finished loading and then need to update the information panel.
How can I ensure that I have this ID before updating the second panel? Currently the information displayed is always one update behind the image!
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ajax concept:
http://www.yourhtmlsource.
(search the page for: callback function, in particular)
Hey hey hey ..
If you are using ASP.Net 2.0 ... why do you want to mess with the XMLHTTP.
There is another way to do this, that I have been using for a long.
Its pretty good.
see, There is something PageRequestManager, and everytime the updatepanel is updated, you come to know by it.
Here you can register a javascript which will update the dependent update panel after the first one is done with it.
var prm = Sys.WebForms.PageRequestMa
prm.add_pageLoaded(pageLoa
and you can write any code in PageLoaded method.
for more help .. pls go and read at the following URL:
http://msdn2.microsoft.com
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by: ZvonkoPosted on 2007-09-18 at 08:26:42ID: 19913731
Call the dependant AJAX call from the callBack handler of the AJAX call that returns the ID.