Custom control not validating
The input parameter is a form control, and the output is either an error object or null if the value is valid.
So here is what that method would look like: The above code defines our directive that implements the Validator interface.
I had already found out that the standard approach (args.value) doesn't work because the value isn't sent to the function from these controls.
I found the following example on a forum somewhere but it only works when the script is in the ascx file. I tried your code just as it was (but with the Data Binder set to one of my DB columns) but got the same error as I had when I had previously tried this myself.
For anybody else copying this, please not that the snippet Princy supplied needs a small modification.
The client validation function property on the custom validator should read: Princy, OK, well you've solved my problem so thanks again.
The error I get is: "Microsoft JScript runtime error: 'client Unit Price Validation' is undefined".
The above form would be invalid as long as the user does not enter a credit card number that passes our validation criteria.
Now let’s add some error handling to render the right error message from our validator function: My name is Alain Chautard.
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