element ui el-table 如何实现带斜线的双表头

实现思路

通过嵌套表头将两个标题设置在一个单元格内，再通过 CSS 样式增加斜线效果。

知识点：el-table、::before、transform

实现的代码

<el-table :data="tableData" border>
	<!--重点代码：采用嵌套的方式-->
   <el-table-column label="数据" align="right" width="150">
     <el-table-column prop="name" label="数据指标" width="150">
     </el-table-column>
   </el-table-column>
   <el-table-column
     v-for="(col, i) in columnList"
     :key="i"
     :prop="col.prop"
     :label="col.label"
     align="center"
   >
     <template v-if="col.children">
       <el-table-column
         v-for="(item, index) in col.children"
         :key="index"
         :prop="item.prop"
         :label="item.label"
       >
       </el-table-column>
     </template>
   </el-table-column>
 </el-table>
 <style scoped>
/*表头斜线*/

	/*::v-deep 这里主要的作用就是用来强制修改element默认的样式*/
	::v-deep  .el-table thead.is-group th {
        background: none;
        padding: 0px;
    }

    ::v-deep .el-table thead.is-group tr:first-of-type th:first-of-type {
        border-bottom: none;/*中间的横线去掉*/
    }

    ::v-deep .el-table thead.is-group tr:first-of-type th:first-of-type div.cell {
        text-align: right;/*上边文字靠右*/
    }

    ::v-deep .el-table thead.is-group tr:last-of-type th:first-of-type div.cell {
        text-align: left;/*下边文字靠左*/
    }
    
	/*核心代码*/
    ::v-deep .el-table thead.is-group tr:first-of-type th:first-of-type:before {
        content: "";
        position: absolute;
        width: 1px;
        height: 80px;/*斜线的长度*/
        top: 0;
        left: 0;
        background-color: #18449C;
        opacity: 1;
        display: block;
        transform: rotate(-61deg);/*调整斜线的角度*/
        -webkit-transform-origin: top;
        transform-origin: top;
    }
	
    ::v-deep .el-table thead.is-group tr:last-of-type th:first-of-type:before {
        content: "";
        position: absolute;
        width: 1px;
        height: 80px;/*斜线的长度*/
        bottom: 0;
        right: 0;
        background-color: #18449C;
        opacity: 1;
        display: block;
        transform: rotate(-62deg);/*调整斜线的角度*/
        -webkit-transform-origin: bottom;
        transform-origin: bottom;
    }
   
</style>