想要实现效果：

目前接口返回数据

data:[{companyCode: "NXKYS",companyName:'1123',costContractId:'1123',costContractName:'1123',createBy:'1123',details:[{brand:'1123',contractItemName:'1123',modelSpec:'1123',projectItemId:'1123',requestQty:'1123',transactionZone:'1123'},{brand:'1123',contractItemName:'1123',modelSpec:'1123',projectItemId:'1123',requestQty:'1123',transactionZone:'1123'},]},{companyCode: "NXKYS",companyName:'1123',costContractId:'1123',costContractName:'1123',createBy:'1123',details:[{brand:'1123',contractItemName:'1123',modelSpec:'1123',projectItemId:'1123',requestQty:'1123',transactionZone:'1123'},{brand:'1123',contractItemName:'1123',modelSpec:'1123',projectItemId:'1123',requestQty:'1123',transactionZone:'1123'},]}]；

其中要根据details这个字段去进行展示图中标记的列。并将其他列进行合并。

首先要重新修改数据格式，方便进行合并以及列表渲染的展示。

接口返回的数据在tableData.value中

计算需要处理子表的数据

const flattenedData = computed(() => {const result = [];const data = tableData.value;if (!data || !Array.isArray(data)) {return result;}data.forEach((mainItem, mainIndex) => {if (mainItem?.details && Array.isArray(mainItem.details) && mainItem.details.length > 0) {mainItem.details.forEach((detail, detailIndex) => {result.push({...mainItem,...detail,_mainIndex: mainIndex,_detailIndex: detailIndex});});} else {result.push({...mainItem,_mainIndex: mainIndex, _detailIndex: 0 // 这是 details 为空时的唯一一行});}});return result;});

el-table中添加span-method方法

<el-table

          ref="tableRef"

          v-loading="tableLoading"

          :data="flattenedData"

          :height="tableHeight"

          :header-cell-style="{ backgroundColor: '#F6F8FC' }"

          highlight-current-row

          :border="props.border"

          v-bind="$attrs"

          @current-change="handleSelectionChange"

          @header-dragend="headerDragend"

          :scrollbar-always-on="true"

          :span-method="objectSpanMethod"

        >

const objectSpanMethod = ({ row, column, rowIndex, columnIndex }) => {const mergeColumns = ['documentCode','costContractId','costContractName','supplierName','handlerDepartmentDesc','projectId','projectName','whName','whCategoryDesc','workflowStateDesc','xz','xh','cz',];const prop = column.property;if (!row) {console.warn('Row is undefined in objectSpanMethod');return { rowspan: 1, colspan: 1 };}if (row._mainIndex === undefined || row._mainIndex === null) {console.warn(`_mainIndex is ${row._mainIndex} for row at index ${rowIndex}`);return { rowspan: 1, colspan: 1 };}if (mergeColumns.includes(prop)) {const mainItemIndex = row._mainIndex;if (!tableData.value || mainItemIndex < 0 ||mainItemIndex >= tableData.value.length ) {console.error('Invalid mainItemIndex or tableData');return { rowspan: 1, colspan: 1 };}const mainItem = tableData.value[mainItemIndex]; if (!mainItem) {console.error(`mainItem is missing for index ${mainItemIndex}`);return { rowspan: 1, colspan: 1 };}const details = mainItem.details || [];const detailCount = details.length;const effectiveRowspan = detailCount > 0 ? detailCount : 1;if (row._detailIndex === 0) {return {rowspan: effectiveRowspan,colspan: 1,};} else {return {rowspan: 0,colspan: 0,};}}return {rowspan: 1,colspan: 1,};
};

mergeColumns定义的是需要进行合并的列的props；

列表渲染就正常展示就可以

如：

 <el-table-column

        prop="transactionZone"

        label="入库分区"

        :show-overflow-tooltip="true"

        width="150"

      >

      </el-table-column>