珠峰2016,第9期 vue.js 笔记部份

在珠峰参加培训好年了,笔记原是记在本子上,现在也经不需要看了,搬家不想带上书和本了,所以把笔记整理下,存在博客中,也顺便复习一下

安装vue.js 

因为方便打包和环境依赖,所以建意npm  init  -y   

第一个示例:

<script src ="./node_modules/vue/dist/vue.js" ></script>
<div id="app">
{{msg==='hello'?1:0}}
</div>
</head>
<body>
<script>
let vm = new Vue({
el:'#app',
data:{
msg:'hello'
}
});

双向绑定及原理:又向绑定只需要在一个可以输入的控件中加入v-model = "",如
<input type = "text v-model = "msg">
__________________________________________
let vm = new Vue({
el:'#app',
data:{
msg:'hello'
}
});

<!--Object.defineProperty--!>

老版本给对象属性定义方法是 var obj.a = "name" 而新版本的defineProperty 则可以在别人获取和得到属性时,触发事件,还有很多配置选项,这是老版本做不到的
新版本定义方法:
Object.defineProperry(obj.'nmae',{
  configurable:True, // 是否能删除
  writeble.true|false ,   //是否能写操作
  enumerable:false, 是否能枚举
// defingProperty,上有二个重要的方法,get(),set() 在设置和 得到属性自动触发
  get(){
      *******************

}
  set(){
      **********************  
}
  value:1
  age:2
})
_________________________________________________________________________________

比如在
get(){
  return 1
}
那么在获取对象性时总是会返回1,在赋值时有一个坑,就是set(var){
  obj.name = "xxx"
}
在赋值时又调用赋值,形成无限循环 ,通常不能在里面给自己赋值,用第三方变解决。。返回和设置时都操作第三方变量,
从而解决自己调用自己的无限循环。。

let obj = {}
let temp = {}
object.defineProperty(obj,"name",{get(){
get(){
  return temp["name"]
}

set(val){
temp["name"]=val; 
})
给绑定一个输入框的例子:仅是原理,工作中用不到
..........................................................
<input type="text" id="input"></input>
.........................................................
let obj = {},
let temp = {},
Object.defineProperty(obj,'name',{
get(){
return temp['name']
}
set(val){ // 给obj 赋值时触发
temp["name" = val]
input.value = obj.name
}
});
input.value = obj.name; //页面加载时,用调用get 方法
input.addEventListener('input',function(){
obj.name = this.value;
})

基础指令。。。。。。。。。。。。。。。。。。。。。。
v-text == {{}} //v-text 界面不闪烁

v-html == <p>xxxx</p>

v-model == "" 双向绑定

v-once 只绑一次

v-for
————————————————————————————————————————————————————————————————————————————
<div id = "app">
<ul>
<li v-for = "f in fruits">{{f.name}}</li>
    //如果要得到index,循环时取二个值,要回括号
    //<li v-for = "(f,index) in fruits"{{f.name}} {{index+1}}></li>
    
</ul>

</div>
<script scr = "......./vue.js"></script>
<script>
let vm = new Vue({
el:"#app",
data:{
fruits:[{name:'xxx'},{name:'yyy'},{name:'ggg'}]
}
})

</script
————————————————————————————————————————————————————————————————————————————

基础todo功能 表单回车后下列菜单自动增加
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<div id = "app">
<input type="text" v-model="val" @keyup = "add">
<ul>
<li v-for = "(a,index) in arr">{{a}}<button@click = "remove(index)">删除</button></li>
</ul>
</div>


</body>
<script src ="./node_modules/vue/dist/vue.js" ></script>
<script>
let vm;
vm = new Vue({
el: '#app',
methods: {
add(e){
if(e.keyCode === 13)this.arr.unshift(this.val);this.val = '';
}

},
data: {
arr: [],
val: '',
}
});


</script>
</html>







数据响应式变化:给对象加属性的三个方法。自动监听,调用自己的get set 方法
let vm = new Vue({
el :'#app',
data:{
a:{school:2} // 1,声明时写
}
});
vm.$set(vm.a,'school',8) // 2.写在这儿
对于要设很多属性的话,可以替换原对象,
vm.a = {school:'zfpx',age:8,address:'xxx'} //3 重写方法

对于数组响应的话,数组元素改变监听不到,常规方法比如
vm.arr[0] = 100
vm.arr.length = -=2
这些变化响化不到数据,只能用变异方法,比如:pop push shift unshift sort reserve splice 能改变数组的方法才行

vm.arr.reverse();
vm.arr = vm.arr.map(item = >item*=3);



简易的todo 例子:
双向绑定实现表单和列表交互,,这儿不作过多解释,把代码复制一下就能看到效果,在一参看,很简单
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<div id = "app">
<input type="text" v-model="val" @keyup.crtl.enter = "add">
<ul>
<li v-for = "(a,index) in arr">{{a}} <button @click = "remove(index)">删除</button></li>
</ul>
</div>


</body>
<script src ="./node_modules/vue/dist/vue.js" ></script>
<script>
let vm;
vm = new Vue({
el: '#app',
methods: {
add(e){
this.arr.unshift(this.val);
this.val = "";
},
remove(i){this.arr = this.arr.filter((item,index)=>index!==i)}

},
data: {
arr: [],
val: '',
}
});


</script>
</html>

第一个AXIOS例子,因为回调函数的this 指向winows 所以用简头函数强制指向主体。
需要说明的二点,1,手工写的json 文件,需要用JSON.stringify() 方法调一下格式,2 忘了,等会补上,为了 节省篇章,代码收缩一下,
<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
<div id = "app">

</div>
</body>
<script src ="./node_modules/vue/dist/vue.js" ></script>
<script src = "./node_modules/axios/dist/axios.js"></script>
<script>
    let vm;
    vm = new Vue({
        el: '#app',
        created(){
            axios.get('./lz.json').then(res=>{
                this.products = res.data;
            },err=>{
                console.log(err);
            });
        },
        data: {
         products:[]
        }
    });
</script>
</html>
View Code

 axios 的原理是利用promise-ajax:

promise是解决回调问题 传统的ajax方法回调太多代码不好看 例:

解决问题 一:

  缓时二秒后给一个变量赋值  a = ‘zzz’,另外的函数打印:通常代码如下

let a = '';

funcion buy(){

  setTimeout()=>{

    let a = "zzzz";

},2000};

buy();

function cookie(){

  //如何在这儿打印  a  的值   ,,技穷了吧!

}

cookie();

!解决这些问题js  只能用回调,,以下方法解决

let a = '';

function buy(callback){

  setTimeout(()=>{

  a = 'yss';

  callback(a);

},2000);

}

buy(function cookie(val){

  console.log(val);

})

以上方法代码不够直观,所以我们开始用要讲的promise   解决这个回调问题。。promise js 自带的,new  promise  就能用

promise  的三个状态 成功,失败,等待

//resolve  成功态

//reject   失败态

let p = new Promise((resolve,reject)=>{

 let a = ‘魔茹’;

  # resolve(a);  成功和失败可以自定义,成功也可以调用reject方法

  reject(a)

},2000)

#p.then((data)=>{console.log(data)},()=>{});

#换个调取方法

p.then((data)=>{console.log(data)},(err)=>{console.log('err')});

女朋友买包实例:

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
<div id = "app">

</div>
</body>
<!--<script src ="./node_modules/vue/dist/vue.js" ></script>-->
<!--<script src = "./node_modules/axios/dist/axios.js"></script>-->
<script>
  function buyPack() {
      return new Promise((resolve,reject)=>{
          setTimeout(()=>{
              if(Math.random()>0.5){
                  resolve('买')
              }else{
                  reject('不买')
              }
          },Math.random()*10000)
      });
  }
buyPack().then(function(data){
    console.log(data);
},function(data){
    console.log(data);
    });

</script>
</html>
浏览器调试运行查看结果

promise-ajax 手工封装ajax示列:

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
<div id = "app">

</div>
</body>
<script src ="./node_modules/vue/dist/vue.js" ></script>
<script src = "./node_modules/axios/dist/axios.js"></script>
<script>
 function ajax({url = "",type='get',dataType = "json"}) {
     return new Promise((resolve,reject)=>{
         let xhr = new XMLHttpRequest();
         xhr.open(type,url,true);
         xhr.responseType =dataType;
         xhr.onload = function(){
             resolve(xhr.response)
             console.log("........................")
         };
         xhr.onerror = function (err) {
             reject(err)
         };
         xhr.send();
     });
 }
 let vm = new Vue({
     el:'#app',
     created(){
         ajax({url:'./lz.json'}).then((res)=>{
             console.log(res)
         },(err)=>{
         })
     },
     data:{
         products:[]
     }
 })




</script>
</html>
View Code

 传统事件外理表单例子:

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@3.3.7/dist/css/bootstrap.min.css"
          integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
    <title>Document</title>
</head>
<body>
<div id = "app">
   <div class="container">
       <div class="row">
           <table class="table table-hover table-bordered">
               <caption class = "h2 text-warning text-center">珠峰购物车</caption>
               <tr>
                   <th>全选<input type="checkbox"></th>
                   <td>商品</td>
                   <td>单价</td>
                   <td>数量</td>
                   <td>小记</td>
                   <td>操作</td>
               </tr>
               <tr v-for ="(product,index) in products">
                   <td><input type="checkbox" v-model="product.isSelected" @change="checkOne"></td>
                   <td><img :src = "product.productCover" :title="product.productCover">  {{product.productName}}</td>
                   <td>{{product.productPrice}}</td>
                   <td><input type="number" v-model.number = "product.productCount"></td>
                   <td>{{product.productCount*product.productPrice | toFixed(2)}}</td>
                   <td><button class="btn btn-danger" @click = "remove(product)">删除</button></td>
               </tr>
               <tr>
                   <td colspan="6">
                       总价格 : {{sum()| toFixed}}
                   </td> </tr>
           </table>
       </div>
   </div>
</div>
</body>
<script src ="./node_modules/vue/dist/vue.js" ></script>
<script src = "./node_modules/axios/dist/axios.js"></script>
<script>
 let vm = new Vue({
     el:'#app',
     filters:{
         toFixed(input,param1){
             return '$'+input.toFixed(param1)
         }
     },
     created() {
         this.getData();
     },
     methods:{
         sum(){
                 return this.products.reduce((prev,next)=>{
                     if(!next.isSelected)return prev;

                     return prev+next.productPrice*next.productCount;
                 },0)
             },

         checkOne(){
             this.checkAll = this.products.every(item=>item.isSelected);
         },
         change(){
             this.products.forEach(item=>item.isSelected = this.checkAll);
         },
         remove(p){
             this.products = this.products.filter(item=>item !==p)
         },
         getData(){
             axios.get('./lz.json').then(res=>{
                 this.products = res.data;
                 this.checkOne();
             },err=>{
                 console.log(err);
             });
         }
     },
     data:{
         products:[],
         checkAll:false,




     }
 })




</script>
</html>
View Code

计算属性外理表单例子:

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@3.3.7/dist/css/bootstrap.min.css"
          integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
    <title>Document</title>
</head>
<body>
<div id = "app">
    <div class="container">
        <div class="row">
            <table class="table table-hover table-bordered">
                <caption class = "h2 text-warning text-center">珠峰购物车</caption>
                <tr>
                    <th>全选<input type="checkbox" v-model="checkAll"></th>
                    <td>商品</td>
                    <td>单价</td>
                    <td>数量</td>
                    <td>小记</td>
                    <td>操作</td>

                </tr>
                <tr v-for ="(product,index) in products">
                    <td><input type="checkbox" v-model="product.isSelected"></td>
                    <td><img :src = "product.productCover" :title="product.productCover">  {{product.productName}}</td>
                    <td>{{product.productPrice}}</td>
                    <td><input type="number" v-model.number = "product.productCount"></td>
                    <td>{{product.productCount*product.productPrice | toFixed(2)}}</td>
                    <td><button class="btn btn-danger" @click = "remove(product)">删除</button></td>
                </tr>
                <tr>
                    <td colspan="6">
                        总价格 : {{sum|toFixed(2)}}
                    </td> </tr>
            </table>
        </div>
    </div>
</div>
</body>
<script src ="./node_modules/vue/dist/vue.js" ></script>
<script src = "./node_modules/axios/dist/axios.js"></script>
<script>
    let vm = new Vue({
        el:'#app',
        filters:{
            toFixed(input,param1){
                return '$'+input.toFixed(param1)
            }
        },
        created() {
            this.getData();
        },
        computed:{
            checkAll:{
                get(){
                    return this.products.every(p=>p.isSelected);
                },
                set(val){
                    this.products.forEach(p=>p.isSelected = val);
                }
            },
            sum:{
                get(){
                    return this.products.reduce((prev,next)=>{
                        if(!next.isSelected)return prev;
                        return prev+next.productPrice*next.productCount;
                },0);
                }
        }
        },
        methods:{
            remove(p){
                console.log('toFixed(2)toFixed(2)'),
                this.products = this.products.filter(item=>item !==p)
            },
            getData(){
                axios.get('./lz.json').then(res=>{
                    this.products = res.data;
                },err=>{
                    console.log(err);
                });
            }
        },
        data:{
            products:[],





        }
    })




</script>
</html>
View Code

vue.js动画处理部份

事件处理部份














原文地址:https://www.cnblogs.com/fgxwan/p/9988651.html