<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML> <HEAD> <TITLE>正则表达式验证小数 </TITLE> </HEAD> <BODY> <script language="JavaScript" type="text/javascript"> function checkNum(obj) { var re = /^-?[1-9]*(\.\d*)?$|^-?d^(\.\d*)?$/; if (!re.test(obj.value)) { if(isNaN(obj.value)){ alert("非法数字"); obj.value=""; obj.focus(); return false; } } } </script> <input name="rate" type="text"onkeyup="checkNum(this)" /> </BODY> </HTML> |
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