vue 功能：点击增加一项，点击减少一项

功能介绍：

默认为一列，当点击右侧"+" 号，增加一列；点击 “-” 号，将当前列删除；

功能截图：

功能代码：

//HTML
<el-col :span="24"><el-form-item label="通道列表：" prop="mobile"><div class="passStreamList"><div class="container" v-for="(item,key) in formDialog.form.passStreamList"><el-input v-model="item.code" type="text" class="dialogFormInputStyle dmzcode" clearable placeholder="编号,只能为数字类型"></el-input> <div class="span"> - </div> <el-input v-model="item.name" type="text" class="dialogFormInputStyle dmzname" clearable placeholder="请输入通道名称"></el-input> <div class="span"> - </div> <el-select v-model="item.type" class="dialogFormInputStyle dmztype" style="width:20%"><el-option v-for="item1 in formDialog.dmzType" :key="item1.id" :label="item1.type" :value="item1.id" placeholder="站类型"><span style="float: left;font-size: 12px">{{item1.type}}</span></el-option></el-select><div class="dmzbutton"><span class="add" @click="passStreamAdd">+</span><span class="reduce" @click="passStreamReduce(key)">-</span></div></div></div></el-form-item>
</el-col>//css.passStreamList{width:100%;.container{width:100%;display:flex;flex-direction: row;justify-content: space-between;.dmzcode,.dmzname{width:28%;cursor: pointer;}div.span{color:#fff;}.dmztype{width:20%;cursor: pointer;}.dmzbutton{display:flex;justify-content: space-around;align-items: center;span{width:25px;height:25px;font-size:20px;background:rgba(155,226,254,0.5);border: 1px solid #9BE2FE;cursor: pointer;color:#fff;text-align:center;line-height:25px;}span:last-child{margin-left:10px;}}}}data(){return {formDialog:{form:{passStreamList:[{}],}}}
},//增加
passStreamAdd(){this.formDialog.form.passStreamList.push({})
},//减少
passStreamReduce(index){let newArr = [];//为一层时禁止减if(this.formDialog.form.passStreamList.length == 1){ return; }if(index == 0){   //为首newArr = this.formDialog.form.passStreamList.slice( 1,this.formDialog.form.passStreamList.length)}else if(index == this.formDialog.form.passStreamList.length-1){  //为尾newArr = this.formDialog.form.passStreamList.slice( 0,this.formDialog.form.passStreamList.length-1)}else{  //为中let arr1 = this.formDialog.form.passStreamList.slice( 0,index)let arr2 = this.formDialog.form.passStreamList.slice( index+1, this.formDialog.form.passStreamList.length)newArr = arr1.concat(arr2)}this.formDialog.form.passStreamList = [].concat(newArr);
},