el-tabs 标签页判断拦截是否阻止tab切换，before-leave

tab切换前，如果有逻辑要处理，不满足条件不允许切，就用before-leave

  <el-tabs type="border-card" :before-leave="confirmLeave">

如果需要表单校验，要用async和await搭配使用，不然校验触发的不及时
如果return false还是切换了，就使用return reject()

  // tab切换前判断async confirmLeave(active) {if (active === '1') {await this.$refs.annualAssetDetail.$refs.costForm.validate(valid => {let arr = this.$refs.annualAssetDetail.costForm.tableDataif (valid) {if (arr.length) {arr.forEach(item => {if (item.clearId == 0) item.id = ''})return true} else {this.$message.warning('请先填写明细数据！')return reject()}} else {for (var i = 0; i < arr.length; i++) {if (!arr[i].Code) {this.$message.warning(`明细数据第${i + 1}行的xx分类未填写！`)break} else if (!arr[i].remark) {this.$message.warning(`明细数据第${i + 1}行的xx说明未填写！`)break}  else {this.$message.warning(`明细数据第${i + 1}行的配置数量未填写！`)}break} }this.formItemVerify(this.$refs.annualAssetDetail.$refs.costForm)return reject()}})} else {this.$refs.annualAssetDetail.costForm.tableDat=[]}},