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Validation in JSP.

 
Ram Kas
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I have a form with 3 fields in a form, UserName, City, Country. Length of each field should not exceed 10 characters. If it exceeds it, the page should be reloaded with error message on the same line of the text box.

Can anybody tell me how I can do it?
 
Chetan Parekh
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<input type="text" maxlength="10" name="text1">

User maxlenght attribute, it will not allow user to enter 11th character at first place.
 
Bear Bibeault
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Unless a malicious user writes his own form to submit to your server.

Point is, client-side validation should never be trusted.

Yes, go ahead and add the maxlength attribute -- that's good for users since they cannot enter too many characters. But also check the length when the code is submitted.

In fact, validation should occur at every layer in the app in case someone is trying to spoof the upper layers. It also makes your code more robust and re-usable.
 
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