ElementUI：el-tabs 切换之前判断是否满足条件

   <div class="table-card">
      <div class="card-steps-class">
        <el-tabs
          v-model="activeTabsIndex"
          :before-leave="beforeHandleTabsClick"
        >
          <el-tab-pane name="1" label="基础设置">
            <span slot="label">
              <span class="span-box">
                <el-tooltip
                  class="item"
                  effect="dark"
                  content="基础设置 "
                  placement="bottom-start"
                >
                  <i class="el-icon-question"></i>
                </el-tooltip>
                <span>基础设置</span>
              </span>
            </span>
          </el-tab-pane>
          <el-tab-pane name="2" label="流程设计">
            <span slot="label">
              <span class="span-box">
                <el-tooltip
                  class="item"
                  effect="dark"
                  content="流程设计 "
                  placement="bottom-start"
                >
                  <i class="el-icon-question"></i>
                </el-tooltip>
                <span>流程设计</span>
              </span>
            </span>
          </el-tab-pane>
          <el-tab-pane name="3" label="高级设置">
            <span slot="label">
              <span class="span-box">
                <el-tooltip
                  class="item"
                  effect="dark"
                  content="高级设置 "
                  placement="bottom-start"
                >
                  <i class="el-icon-question"></i>
                </el-tooltip>
                <span>高级设置</span>
              </span>
            </span>
          </el-tab-pane>
        </el-tabs>
      </div>

关键代码： 

增加业务逻辑，调用子组件表单验证~~~ 

 methods: {
    beforeHandleTabsClick: function (index) {
      if (this.activeTabsIndex === "1" && (index === "2" || index === "3")) {
        let reValidState = this.$refs.baseForm.sumbitForm();
        if (reValidState) {
          this.activeTabsIndex = index;
          return true;
        }
        return false;
      } else if (
        this.activeTabsIndex === "2" &&
        (index === "1" || index === "3")
      ) {
        return true;
      }
    },
}