解决表头缺失的时候上边框消失的问题—待测试

src/baseComponents/Table.vue

@@ -1,7 +1,9 @@
 <template>
     <div class="page_table">
         <!-- :height="tableHeight" -->
+          <!-- border -->
         <el-table 
+          class="el-table--border"
           :show-header="showHeader"
           :data="props.tableData" stripe v-loading="props.loading" element-loading-text="拼命加载中……" 
           element-loading-spinner="el-icon-loading" element-loading-background="#ffffff"