限制input小数点及位数

摘要：小数点限制两位小数正整数限定为正整数动态添加了内容要用事件委托方式绑定下面的事件保留至多两个小数点的数字显示效果说明适用于多种情况判断

HTML

    
    
    
    
    
    
    



    

    

        

            

                两位小数：
                正整数：
            
        
    
    
    
     
    

JS

function amountInput(parent,child) {
    var CashingAmountLast = "";

    $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, 10);
                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);
            }
        })();
    }
}

显示效果

说明
适用于多种情况判断