Client Side Validation on date picked to show a textbox in asp.net
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I'm trying to add validation to a date textbox, where if the current date picked is less than present date, a textbox appears for additional information. 

I've been able to add a custom validation to it, but it only works on hitting the submit button, I'd like to know if there is a way where we can validate the date when picked to show the textbox in a dynamic way rather then hitting the submit button for the textbox to be generated.

