<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <title>Document</title> <script src="./Kvue.js" type="text/javascript"></script> </head> <body> <div id="app"> {{ message }}fsdafdsa <div> <span> <span> <span> {{ message }}</span> </span> </span> </div> {{mydata}} <div v-html="htmldata" ></div> <input v-model="modelData" /> {{modelData}} </div> </body> <script> let vm = new Kvue({ el:"#app", data:{ message:"测试数据1111", mydata:"some value", htmldata:"html数据", modelData:"双绑数据" } }) </script>
class Kvue{ constructor(option){ this.option=option; this._data=option.data; this.observer(); this.compile(); } //编译 compile(){ let ele=document.querySelector(this.option.el); let childNodes=ele.childNodes; this.compileNode(childNodes); } //对数据编译到元素上 compileNode(childNodes){ let textContent=""; let exp=null; childNodes.forEach((node,index)=>{ if(node.nodeType==3){ textContent= node.textContent; exp=/\{\{\s*(\S+)\s*\}\}/g; if(exp.test(textContent)){ // 初次渲染； let $1 = RegExp.$1; node.textContent=this._data[$1]; new Watcher(this,$1,newValue=>{ node.textContent=newValue; }); } } else if(node.nodeType==1){ let attrs= node.attributes; [...attrs].forEach((attr,index)=>{ let name= attr.name; let value= attr.value; if(name=="v-model"){ node.addEventListener("input",ev=>{ this._data[value]=ev.target.value; }); new Watcher(this,value,newValue=>{ node.value=newValue; }); } }); if(node.childNodes.length>0){ this.compileNode(node.childNodes); } } }); } observer(){ Object.keys(this._data).forEach((key)=>{ let dep=new Dep(); let value= this.option.data[key]; Object.defineProperty(this._data,key,{ configurable: true, enumerable: true, get(){ if(Dep.target){ dep.addSub(Dep.target); } return value; }, set(newValue){ if(value!=newValue){ dep.notify(newValue); value=newValue; } } }); }) } } //发布订阅 Dep 类和 Watcher class Dep{ constructor(){ this.subs=[]; } addSub(sub) {//订阅事件 this.subs.push(sub); } notify(newValue) {//通知触发方法 this.subs.forEach(v => { v.update(newValue); }) } } class Watcher { constructor(vm, exp, cb) { Dep.target = this; vm._data[exp]; this.cb = cb; Dep.target = null } update(newValue) { this.cb(newValue); } }
原文：https://www.cnblogs.com/supermanGuo/p/11448998.html