验证小数点后两位，且是正数

*******只能输入小数点后两位 且是正整数

function amountInput(parent,child,maxLength) {
var CashingAmountLast = "";
if(maxLength == undefined)
{
maxLength = 10;
}
$moneyInput = ""; //动态添加了内容 要用事件委托方式绑定下面的事件

function checkCode(code) {
var codeArea = code > 57 && code < 96;
if (!(code == 190 || code == 110 || code == 46 || code == 8 || code == 37 || code == 39)) {
if (codeArea || code < 48 || code > 105) {
return false;
}
}
return true;
}

$(parent).on("keydown", child, function(e) {
var code = e.keyCode,
val = e.target.value;
if (val.indexOf(".") > -1 && (code == 190 || code == 110)) {
e.target.value = val;
return false;
}
if (!checkCode(code)) {
return false;
}
this.setAttribute("data-keyCode", code);
return true;
}).on("input",child, function(e) {
var val = this.value,
keyCode = this.getAttribute("data-keyCode"),
reSet = false;
if (e.currentTarget.validity.valid) {
if (val.indexOf(".") < 0 && (keyCode == 190 || keyCode == 110)) {
val += ".";
}
} else {
val = CashingAmountLast;
if ((keyCode == 190 || keyCode == 110) && val.indexOf(".") < 0) {
val = Number(CashingAmountLast).toFixed(1);
}
reSet = true;
}
fixCashFn.call(this,val, reSet);
}).on("blur", child,function(e) {
var val = Number($(this).val());
if (!isNaN(val)) {
e.target.value = val;
} else {
e.target.value = 0;
}
});

function fixCashFn(a, isReset) {
let money = typeof a === "string" ? a : a.toString(),
flag = false,
valArr = [],
_slef = this;
money = money.replace(/s/g, "");
var strLen = money.length;
if (isNaN(Number(money))) {
flag = true;
} else if (strLen > 0) {
//保留至多两个小数点的数字
if (!/^d+(?:.d{1,2})?$/.test(money) && money.charAt(strLen - 1) !== ".") {
flag = true;
}
}
if (flag) {
money = CashingAmountLast;
}
if (isNaN(Number(money))) {
money = "";
}
(function() {
if (money.length > 0) {
valArr = money.split(".");
money = Number(valArr[0]).toString().slice(0, maxLength);
if (valArr.length > 1) {
money += "." + valArr[1].slice(0, 2);
}
}
if (money.charAt(money.length - 1) !== ".") {
if (a !== money) {
$(_slef).val(money);
CashingAmountLast = money;
} else {
CashingAmountLast = a;
}
}
if (isReset) {
$(_slef).val(money);
}
})();
}
}

*****用法

amountInput("#EditReCon_PayFormId",".EditReCon_PayMoney",10);//form表单id ，验证输入框的class ，只能输入几位数