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HTML

              
                <h2>
  The person below will change in <span id='timer'>5</span> seconds</h2>
<!-- 下面是 mvvm 中的 View层 -->
<!-- View层 start -->
<div>Name: <span id="name">Nelson Kuang</span></div>
<div>Age: <span id="age">18</span></div>
<div id="classmates">
  <h3>Classmates</h3>
  <table>
    <thead>
      <tr>
        <th>Name</th>
        <th>Gender</th>
        <th>Age</th>
      </tr>
    </thead>
    <tbody id="classmates__list">
      <tr>
        <td>张三</td>
        <td>男</td>
        <td>18</td>
      </tr>
      <tr>
        <td>李四</td>
        <td>男</td>
        <td>17</td>
      </tr>
      <tr>
        <td>王五</td>
        <td>女</td>
        <td>19</td>
      </tr>
    </tbody>
  </table>
</div>
<div id="school">
  <h3>XX Middle School</h3>
  <ul>
    <li>Class 18</li>
    <li>Grade 03</li>
  </ul>
  <h3>Courses</h3>
  <table>
    <thead>
      <tr><th>时间</th><th>周一</th><th>周二</th><th>周三</th><th>周四</th><th>周五</th></tr>
    </thead>
    <tbody>
      <!--<tr><td>第一节<br>xx:xx-xx:xx</td><td>语文</td><td>语文</td><td>语文</td><td>语文</td><td>语文</td></tr>-->
    </tbody>
  </table>
</div>
<!-- View层 end -->
              
            
!

CSS

              
                table {
  border: 1px solid #ddd;
  border-collapse: collapse;
}
td, th {
  border: 1px solid #ddd;
}
ul, li {
  list-style: none;
}
              
            
!

JS

              
                // --- View层 请看Html代码段
// --------- Model层 ----------
var newPerson = {
  name: 'Nelson Kuang',
  age: 18,
  classMates: [
    {
      name: '张三',
      gender: '男',
      age: 18
    },
    {
      name: '李四',
      gender: '男',
      age: 17
    },
    {
      name: '王五',
      gender: '女',
      age: 19
    }
  ],
  school: {
    name: 'XX Middle School',
    classNumber: '18',
    grade: '03',
    courses: [
       // {time: 'xx:xx-xx:xx',activity: '第一节',type: 'regular', Monday: '语文', Tuesday: '数学', Wednesday: '英语', Thursday: '化学', Friday: '物理'}
      ]
  }
};

// --------- viewModel层 ----------
function updateSchool(newVal, oldVal) { // 传统的拼接html字符串的方式实现更新视图View
  console.log(newVal)
  var compiled = _.template('<h3><% name %></h3><ul><li>Class <% classNumber %></li><li>Grade <% grade %></li></ul><h3>Courses</h3><table><thead><tr><th>时间</th><th>周一</th><th>周二</th><th>周三</th><th>周四</th><th>周五</th></tr></thead><tbody><% _.forEach(courses, function(course) { %><tr><th><%- course.activity %><br><%- course.time %></th><td><%- course.Monday %></td><td><%- course.Tuesday %></td><td><%- course.Wednesday %></td><td><%- course.Thursday %></td><td><%- course.Friday %></td></tr><% }); %></tbody></table>')
  document.querySelector('#school').innerHTML = compiled(newVal)
}
Object.defineProperty(newPerson, 'school', {
    set: function (x) {
        if (!_.isEqual(x, this.oldPropValue)) { // 数组或者对象的比较与普通的数值的比较不一样,要深度遍历进行比较
          console.log(x)
          updateSchool(x, this.oldPropValue)
          this.oldPropValue = x
        } else {
            console.log('school的值没变')
        }
    },
    get: function () {
        console.log('in property get accessor');
        return this.oldPropValue;
    },
    enumerable: true,
    configurable: true
});


function updateTable(newVal, oldVal) { // 传统的拼接html字符串的方式实现更新视图View
  if(_.isArray(newVal)) {
    var el = document.querySelector('#classmates__list'),
        strHtml = '';
    newVal.forEach(function(item){
      strHtml += '<tr><td>' + item.name + '</td><td>' + item.gender + '</td><td>' + item.age + '</td></tr>';
    })
    el.innerHTML = strHtml
  }
}
Object.defineProperty(newPerson, 'classMates', {
    set: function (x) {
        if (!_.isEqual(x, this.oldPropValue)) { // 数组或者对象的比较与普通的数值的比较不一样,要深度遍历进行比较
          updateTable(x, this.oldPropValue)
          this.oldPropValue = x
        } else {
            console.log('classMates的值没变')
        }
    },
    get: function () {
        console.log('in property get accessor');
        return this.oldPropValue;
    },
    enumerable: true,
    configurable: true
});


Object.defineProperty(newPerson, 'name', {
    set: function (x) {
        if (x !== this.oldPropValue) {
            document.querySelector('#name').innerHTML = x
            this.oldPropValue = x;
        } else {
            console.log('name的值没变')
        }
    },
    get: function () {
        console.log('in property get accessor');
        return this.oldPropValue;
    },
    enumerable: true,
    configurable: true
});
Object.defineProperty(newPerson, 'age', {
    set: function (x) {
        if (x !== this.oldPropValue) {
            document.querySelector('#age').innerHTML = x
            this.oldPropValue = x;
        } else {
            console.log('age的值没变')
        }
    },
    get: function () {
        console.log('in property get accessor');
        return this.oldPropValue;
    },
    enumerable: true,
    configurable: true
});
// --------- mvvm 数据驱动开发方式,现在只需修改newPerson的数据,View层的Dom节点会自动更新,如下:
  setTimeout(function(){
    // mvvm 数据驱动开发方式
    newPerson.name = 'Gary Li'
    newPerson.age = 20
    newPerson.classMates = [
    {
      name: '小明',
      gender: '男',
      age: 17
    },
    {
      name: '小强',
      gender: '男',
      age: 19
    },
    {
      name: '小梅',
      gender: '女',
      age: 19
    }]
    newPerson.school = {
      name: 'YY Middle School',
      classNumber: '10',
      grade: '01',
      courses: [
         {time: '8:00-8:45',activity: '第一节',type: 'regular', Monday: '语文', Tuesday: '数学', Wednesday: '英语', Thursday: '化学', Friday: '物理'},
         {time: '8:55-9:45',activity: '第二节',type: 'regular', Monday: '物理', Tuesday: '数学', Wednesday: '数学', Thursday: '数学', Friday: '数学'},
         {time: '10:00-10:45',activity: '第三节',type: 'regular', Monday: '化学', Tuesday: '英语', Wednesday: '英语', Thursday: '英语', Friday: '英语'},
         {time: '11:05-11:50',activity: '第四节',type: 'regular', Monday: '数学', Tuesday: '语文', Wednesday: '语文', Thursday: '语文', Friday: '语文'},
         {time: '14:00-14:45',activity: '第五节',type: 'regular', Monday: '英语', Tuesday: '英语', Wednesday: '英语', Thursday: '物理', Friday: '数学'},
         {time: '14:55-15:40',activity: '第六节',type: 'regular', Monday: '化学', Tuesday: '物理', Wednesday: '物理', Thursday: '英语', Friday: '物理'},
         {time: '15:50-16:35',activity: '第七节',type: 'regular', Monday: '物理', Tuesday: '英语', Wednesday: '语文', Thursday: '物理', Friday: '数学'}
        ]
    }
  }, 5000)


// 下面只是计时器,与上面无关,set the timer
Object.prototype.delay = function (time, doSomething) {
    var self = this,
        startTime = time;
    if (self) {
        setTimeout(function () {
            doSomething(self, startTime);
        }, time);
    }
    return this;
}
var el = document.querySelector('#timer');
for (var i = 0; i <= 5; i++) {
    el.delay(i * 1000, function (self, startTime) {
        self.innerHTML = 5 - startTime / 1000;
    })
}
              
            
!
999px

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