动态新增input输入框

        实现原理，修改绑定数组的长度。

        需要绑定的数组

 memberList: [
                        {
                            userName: '',
                            phone: '',
                            position: ''
                        }
                    ],

        点击时触发修改绑定数组长度的方法

            addItem() {
                    this.memberList.push({name: '', phone: '', post: ''})
            },

            deleteItem(item, index) {
                this.inputForm.memberList.splice(index, 1)
            },

        页面上绑定点击事件的组件，和动态绑定数组的组件

<el-card>
            <spean>添加成员</spean>
            <div v-for="(input, index) in memberList" :key="index" style="margin-left: 15vh">
                <el-row :gutter="1">
                    <el-col :span="7">
                        <el-form-item label="名字" prop="userName" class="foritem" label-width="45px">
                            <el-input v-model="input.userName"></el-input>
                        </el-form-item>
                    </el-col>
                    <el-col :span="7">
                        <el-form-item label="职务" prop="position" class="foritem" label-width="45px">
                            <el-input v-model="input.position"></el-input>
                        </el-form-item>
                    </el-col>
                    <el-col :span="7">
                        <el-form-item label="电话" prop="phone" class="foritem" label-width="45px">
                            <el-input v-model="input.phone"></el-input>
                        </el-form-item>
                    </el-col>

                    <el-col :span="3">
                        <el-form-item class="foritem" label-width="20px">
                            <el-tag type="primary"
                                    size="mini"
                                    @click="addItem()">+
                            </el-tag>
                            <el-tag v-if="index !== 0" type="danger" size="mini" @click="deleteItem(item, index)">-
                            </el-tag>
                        </el-form-item>
                    </el-col>
                </el-row>
            </div>
        </el-card>