<el-form-item label="标题：">
   <el-select 
        placeholder="请选择" 
        multiple 
        style="width:100%" 
        v-model="queryParams.craftId" 
        size="mini" 
        @change="processingTechnic">
            <el-option
               v-for="item in processingTechnicOptions" 
               :key="item.id" 
               :label="item.name"
               :value="item.id"
             />
    </el-select>
</el-form-item>

data() {
    return {
        processingTechnicOptions:[],
        craftName:'',
        craftId:[],
        craftNames:[],
    }
},
methods:{
    // 方法1
    processingTechnic(val){
      var names = "";
      for(let i=0;i<=val.length-1;i++){
        this.processingTechnicOptions.find((item)=>{
          if(item.id == val[i]){
            names += item.name + ",";
          }
        });
      }
      this.craftName = names;
    },
    
    // 方法2
    processingTechnic(val){
      this.craftId = [];
      this.craftNames= [];
      for(let i=0;i<=val.length-1;i++){
        this.processingTechnicOptions.find((item)=>{
          if(item.id == val[i]){
            this.craftId.push(item.id);
            this.craftNames.push(item.name);
          }
        });
      }
      console.log(this.craftId)
      console.log(this.craftNames)
    },
},