easyexcel 列宽合并单元格

以下是使用EasyExcel实现列宽和合并单元格的示例代码：

1. 自定义列宽

// 继承AbstractHeadColumnWidthStyleStrategy类
public class CustomHeadColumnWidthStyleStrategy extends AbstractHeadColumnWidthStyleStrategy {

    // 设置第1列的宽度为20
    @Override
    protected void setColumnWidth(WriteSheetHolder writeSheetHolder, List<ColumnWidthData> columnWidthDataList) {
        columnWidthDataList.add(new ColumnWidthData(20));
    }
}

2. 合并单元格

// 继承AbstractMergeStrategy类
public class CustomMergeStrategy extends AbstractMergeStrategy {

    // 合并第1行到第2行的第1列到第3列
    @Override
    protected void merge(Sheet sheet, Cell cell, Head head, Integer relativeRowIndex) {
        if (cell.getRowIndex() == 0 && cell.getColumnIndex() == 0) {
            CellRangeAddress cellRangeAddress = new CellRangeAddress(0, 1, 0, 2);
            sheet.addMergedRegion(cellRangeAddress);
        }
    }
}

在写入Excel时，使用自定义的列宽和合并策略：

// 自定义列宽和合并策略
CustomHeadColumnWidthStyleStrategy customHeadColumnWidthStyleStrategy = new CustomHeadColumnWidthStyleStrategy();
CustomMergeStrategy customMergeStrategy = new CustomMergeStrategy();

// 写入Excel
EasyExcel.write(fileName, DemoData.class)
        .registerWriteHandler(customHeadColumnWidthStyleStrategy)
        .registerWriteHandler(customMergeStrategy)
        .sheet().doWrite(dataList);