关于vue.js:vue2-element-ui-input输入格式限制

import Vue from "vue";/** * element-input 输出限度 * *///v-positiveInteger  正整数//v-positiveInteger.2  保留两位小数//v-positiveInteger.4  保留四位小数Vue.directive("positiveInteger", {    bind(el, binding, vnode) {        let dom = findDom(el, "el-input__inner");        let modifiers = binding.modifiers        let mantissa = 0        for (let x in modifiers) {            mantissa = x        }        el.handler = function () {            if (vnode.inputLocking) {                return;            }            if(mantissa) {                let reg = new RegExp(`^\\D*(\\d*(?:\.\\d{0,${mantissa}})?).*$`, 'gmi')                el.childNodes[1].value = el.childNodes[1].value.replace(reg, "$1");            }else {                el.childNodes[1].value = el.childNodes[1].value.replace(/\D+/g, "");            }                    };        dom.addEventListener("compositionstart", () => {            vnode.inputLocking = true;        });        dom.addEventListener("compositionend", () => {            vnode.inputLocking = false;            dom.dispatchEvent(new Event("input"));        });        dom.onfocus = function () {            if (dom.value == 0) {                dom.value = "";            }        };        el.addEventListener("keyup", el.handler);        el.handler1 = function () {            el.childNodes[1].value = el.childNodes[1].value;            dom.dispatchEvent(new Event("input"));        };        el.childNodes[1].addEventListener("blur", el.handler1);    },    unbind(el) {        el.removeEventListener("keyup", el.handler);        el.childNodes[1].removeEventListener("blur", el.handler);    },});//递归查找某个元素节点function findDom(el, className) {    let dom;    for (let i = 0; i < el.childNodes.length; i++) {        if (el.childNodes[i].nodeType == 1) {            let str = el.childNodes[i].getAttribute("class");            if (str.indexOf(className) > -1) {                dom = el.childNodes[i];                break;            } else {                dom = findDom(el.childNodes[i], className);            }        }    }    return dom;}

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