http://www.iteye.com/news/23823
https://www.cnblogs.com/xumanbu/p/5019474.html
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<script type="text/javascript">
var reg = /(^[1-9]([0-9]+)?(\.[0-9]{1,2})?$)|(^(0){1}$)|(^[0-9]\.[0-9]([0-9])?$)/;
var money = "520.100";
//000 错
//0 对
//0. 错
//0.0 对
//050 错
//00050.12错
//70.1 对
//70.11 对
//70.111错
//500 正确
if (reg.test(money)) {
alert("正确~");
}else{
alert("有误~");
};
</script>
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