requiredfieldvalidater validates textbox whos value is set with javascript

I have a requiredfieldvalidator that validates a text box. The text in the textbox is set through one way only: a javascript places a value in it.


The textbox successfully gets a value when the javascript runs. I use the following code in the javascript:
form1.Wizard1$txtLeftScan.value = "Scan Aquired"


But when I try to navigate away from the current page, the requiredfieldvalidator does not allow it. And the textbox is emptied.


Is this because postback is causing the page to refresh and thus the field appears empty by the time the requiredfield validator has a chance to do its job? Why would it matter whether I enter info into the textbox manually or with a javascript?


Thanks,
Sam
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