<script> var re = new RegExp(/^[-\+]?\d+$/); var str="-654645"; var isZhengShu= re.exec(str); if(isZhengShu)alert(isZhengShu+"是整数!"); </script>
<script> var re = new RegExp(/^[-\+]?\d+(\.\d+)?$/); var str="-234.32423"; var isZhengShu= re.exec(str); if(isZhengShu) alert(str+"是实数!"); else alert(str+"不是实数!"); </script>
var re = new RegExp(/^[-\+]?\d+$/);
var str="-654645";
var isZhengShu= re.exec(str);
if(isZhengShu)alert(isZhengShu+"是整数!");
</script>
var re = new RegExp(/^[-\+]?\d+(\.\d+)?$/);
var str="-234.32423";
var isZhengShu= re.exec(str);
if(isZhengShu) alert(str+"是实数!");
else alert(str+"不是实数!");
</script>
Double.parseDouble(String s)
的方法,如果不抛出 NumberFormatException 异常,说明是数字。
<input onkeyup="this.value=this.value.replace(/\D/g,'')" onafterpaste="this.value=this.value.replace(/\D/g,'')">2.直接用函数
isNaN(arg0)
返回
true:非数字;
<head>
</head>
<script>
function ff()
{
var code=event.keyCode;
if(code<49 || code>59&&code<97 || code>107)
{
event.returnValue=false;
}
}
</script>
<body>
<form>
<input type="text" onkeydown="ff()">
</form>
</body>
</html>
function checkInteger(theField, fieldName) {
var pattern = /^(\d|(-\d))\d*$/; if(theField.value == "") return true;
if (!pattern.test(theField.value)) {
alert(fieldName + "必须为整数!");
theField.focus();
theField.select();
return false;
} return true;
}