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To enforce keyboard entry so that users can only input numerical values for a text field
Code:
There are several online resources online that describe this (e.g. http://stackoverflow.com/questions/995183/how-to-allow-only-numeric-0-9-in-html-inputbox-using-jquery, http://snipt.net/GerryEng/jquery-making-textfield-only-accept-numeric-values, etc.).
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