浅谈vue的props,data,computed变化对组件更新的影响

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本文介绍了vue的props,data,computed变化对组件更新的影响,分享给大家,废话不多说,直接上代码

/** this is Parent.vue */
<template>
 <div>
  <div>{{'parent data : ' + parentData}}</div>
  <div>{{'parent to children1 props : ' + parentToChildren1Props}}</div>
  <div>{{'parent to children2 props : ' + parentToChildren2Props}}</div>
  <div>
   <el-button @click="changeParentData">change parent data</el-button>
   <el-button @click="changeParentToChildren1Props">change parent to children1 data</el-button>
   <el-button @click="changeParentToChildren2Props">change parent to children2 data</el-button>
  </div>
  <my-children1 :children1Props="parentToChildren1Props" @changeParentToChildren1Props="changeParentToChildren1Props"></my-children1>
  <my-children2 :children2Props="parentToChildren2Props" @changeParentToChildren2Props="changeParentToChildren2Props"></my-children2>
 </div>
</template>

<script>
 import Children1 from './Children1';
 import Children2 from './Children2';
 export default{
  name: 'parent',
  data() {
   return {
    parentData: 'ParentData',
    parentToChildren1Props: 'ParentToChildren1Props',
    parentToChildren2Props: 'ParentToChildren2Props'
   }

  },

  beforeCreate: function() {
   console.log('*******this is parent beforeCreate*********');

  },

  created: function() {
   console.log('######this is parent created######');

  },

  beforeMount: function() {
   console.log('------this is parent beforeMount------');

  },

  mounted: function() {
   console.log('++++++this is parent mounted++++++++');

  },

  beforeUpdate: function() {
   console.log('&&&&&&&&this is parent beforeUpdate&&&&&&&&');

  },

  updated: function() {
   console.log('$$$$$$$this is parent updated$$$$$$$$');

  },

  methods: {
   changeParentData: function() {
    this.parentData = 'changeParentData'

   },

   changeParentToChildren1Props: function() {
    this.parentToChildren1Props = 'changeParentToChildren1Props'

   },

   changeParentToChildren2Props: function() {
    this.parentToChildren2Props = 'changeParentToChildren2Props'

   }

  },
  components: {
   'my-children1': Children1,
   'my-children2': Children2
  }
 }
</script> 

/** this is Children1.vue */
<template>
 <div>
  <div>{{'children1 data : ' + children1Data}}</div>
  <div>{{'parent to children1 props : ' + children1Props}}</div>
  <div>{{'parent to children1 props to data : ' + children1PropsData}}</div>
  <div>
   <el-button @click.native="changeChildren1Data">change children1 data</el-button>
   <el-button @click.native="emitParentToChangeChildren1Props">emit parent to change children1 props</el-button>
  </div>
 </div>
</template>

<script>
 export default {
  name: 'children1',
  props: ['children1Props'],
  data() {
   return {
    children1Data: 'Children1Data'
   }
  },

  computed: {
   children1PropsData: function() {
    return this.children1Props
   }
  },

  beforeCreate: function() {
   console.log('*******this is children1 beforeCreate*********');

  },

  created: function() {

   console.log('######this is children1 created######');
  },

  beforeMount: function() {
   console.log('------this is children1 beforeMount------');

  },

  mounted: function() {
   console.log('++++++this is children1 mounted++++++++');

  },

  beforeUpdate: function() {
   console.log('&&&&&&&&this is children1 beforeUpdate&&&&&&&&');

  },

  updated: function() {
   console.log('$$$$$$$this is children1 updated$$$$$$$$');

  },

  methods: {
   changeChildren1Data: function() {
    this.children1Data = 'changeChildren1Data'

   },

   emitParentToChangeChildren1Props: function() {
    console.log('emitParentToChangeChildren1Props');
    this.$emit('changeParentToChildren1Props');
   }
  }
 }
</script> 

/** this is Children2.vue */
<template>
 <div>
  <div>{{'children2 data : ' + children2Data}}</div>
  <div>{{'parent to children2 props : ' + children2Props}}</div>
  <div>{{'parent to children2 props to data : ' + children2PropsData}}</div>
  <div>
   <el-button @click.native="changeChildren2Data">change children2 data</el-button>
   <el-button @click.native="emitParentToChangeChildren2Props">emit parent to change children2 props</el-button>
  </div>
 </div>
</template>

<script>
 export default {
  name: 'children2',
  props: ['children2Props'],
  data() {
   return {
    children2Data: 'Children2Data',
    children2PropsData: this.children2Props
   }
  },

  beforeCreate: function() {
   console.log('*******this is children2 beforeCreate*********');

  },

  created: function() {
   console.log('######this is children2 created######');

  },

  beforeMount: function() {
   console.log('------this is children2 beforeMount------');

  },

  mounted: function() {
   console.log('++++++this is children2 mounted++++++++');

  },

  beforeUpdate: function() {
   console.log('&&&&&&&&this is children2 beforeUpdate&&&&&&&&');

  },
  updated: function() {
   console.log('$$$$$$$this is children2 updated$$$$$$$$');

  },

  methods: {
   changeChildren2Data: function() {
    this.children2Data = 'changeChildren2Data'
   },

   emitParentToChangeChildren2Props: function() {
    this.$emit('changeParentToChildren2Props');
   }
  }
 }
</script> 
  1. 父组件改变props,子组件如果直接使用props,会触发子组件更新
  2. 父组件改变props,子组件如果将props放进data中再使用,不会触发子组件更新
  3. 父组件改变props,子组件如果将props放进computed中再使用,会触发子组件更新
  4. data,props和computed的变化都会触发组件更新

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。

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