Accepting zero as a value

I have a form, and one input is amount. I want to开发者_开发问答 be able to use 0 as a price, but if I use zero, I get an error as set by me that I cannot leave the input blank.

The field is set as int(10).

Thanks

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Post your code for validating the field. You may want to use !=='' or isset() instead of empty() or if($_POST[val])

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You can use -1 for the default value that represents no amount entry.