vue中$set与$delete的使用及说明

var vm = new vue({
  data:{
    a:1
  }
})
 
// `vm.a` 是响应式的
 
vm.b = 2
// `vm.b` 是非响应式的

vue.set(vm.someObject, "b" ,2)

this.$set(this.someObject, "b", 2)

this.someObject = Object.assign({},this.someObject,{a:1,b:2})

            <div class>
              参数名：
              <el-input style="width:170px" v-model="parKey" class="margin_r20"></el-input>参数值：
              <el-input style="width:170px" v-model="parName" class="margin_r10"></el-input>
              <el-button type="primary" size="medium" @click="addPar">增加</el-button>
            </div>参数列表
            <ul class="parList">
              <li v-for="(value, name, index) in AddEditeDialog.netTypeParam" :key="index">
                {{name}} : {{value}}
                <el-button size="mini" round @click="delPar(name)" class="pull-right">删除</el-button>
              </li>
            </ul>

    addPar() {
      this.parKey = this.parKey.trim();
      this.parName = this.parName.trim();    
      this.$set(this.AddEditeDialog.netTypeParam, this.parKey, this.parName);
      // 不能写成this.AddEditeDialog.netTypeParam[this.parKey] = this.parKey
      this.parKey = "";
      this.parName = "";
    },
    delPar(name) {
      this.$delete(this.AddEditeDialog.netTypeParam, name);
    },

vm.items[indexOfItem] = newValue
vm.items.length = newLength

var vm = new vue({
  data: {
    items: ['a', 'b', 'c']
  }
})
vm.items[1] = 'x' // 不是响应性的
vm.items.length = 2 // 不是响应性的

vm.items[indexOfItem] = newvue
// 可以采用下面2种方法实现响应式
Vue.set(vm.items, indexOfItem, newValue) || vm.$set(vm.items, indexOfItem, newValue)
vm.items.splice(indexOfItem, 1, newValue)
 
vm.items.length = newLength
// 可以采用下面方法实现响应式
vm.items.splice(newLenght)