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ajax control toolkit watermark extender in update panel

I have a web page that initially loads a drop down list. When an item is selected from the list, a web form is dynamically created during an update panel async postback.

I added watermark extenders to some of the textboxes, but the watermark does not display when the page is first updated. If I focus in and then out of one of the textboxes, the watermark then appears and seems to work fine. From examining the source, I saw that the client side creation of the watermark was being attached to the init event of Sys.Application on the client.

Here's where I'm getting confused. 1. I added a handler to the client side page Sys.Application.initialize event to see if it was called during the life cycle of an async postback. It didn't appear to fire the event. 2. I tried to raise the initialize 开发者_运维技巧event by adding a handler to the PageRequestManager End Request method, but the flags that check if the page was already initialized were set, so none of the individual handlers were fired. 3. After 1 & 2, I thought maybe the watermark extender was somehow being lazy loaded when I applied focus to it. So I put the $create statement that is supposed to be executed in the initialize event in the End Request event of the PageRequestManager. The client script threw an error because the watermark extender was apparantly already created.

I'm not sure what the resolution here is, outside of writing my own watermark code. Is this a limitation (will the extender only function correctly if created in the initial request for the page)? And what about the init event? I can't see it firing, but if the extender was already created, it must have???

Any help would be appreciated. Thanks.


The watermark extension gives headaches to others too. I'd suggest taking a look at a jquery watermark plugin http://jquery-watermark.googlecode.com/

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