EasyExcel合并单元格（一）

本是古典何须时尚 2023-02-08 12:40 11阅读 0赞

# 前言 #

导出excel，介绍如何使用LoopMergeStrategy实现简单的合并

## 效果 ##

### 每隔2行，合并一次 ###

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyNzQ3MjEw_size_16_color_FFFFFF_t_70]

### 横向合并 ###

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyNzQ3MjEw_size_16_color_FFFFFF_t_70 1]

### 横向和纵向合并 ###

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyNzQ3MjEw_size_16_color_FFFFFF_t_70 2]

## 实现 ##

### 导入依赖 ###

<dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>easyexcel</artifactId>
                <version>2.2.7</version>
            </dependency>
    
            
            <dependency>
                <groupId>com.google.guava</groupId>
                <artifactId>guava</artifactId>
                <version>30.1-jre</version>
            </dependency>
    
            
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
            </dependency>

### 单元测试 ###

/**
     * 合并单元格
     * @date 01/31/2021 03:11
     */
    public class Demo {
        
    
        /**
         * 合并单元格
         */
        @Test
        public void testMyMergeWrite() {
        
    
            String fileName = "/Users/quanlinglong/Downloads/mergeDemo/" + "mymergeWrite" + System.currentTimeMillis() + ".xlsx";
            System.out.println("fileName = " + fileName);
    
            // 每隔2行合并一次，横向合并1列，从第0列开始
    //        LoopMergeStrategy loopMergeStrategy = new LoopMergeStrategy(2, 1, 0);
            // 上面的等价于
    //        LoopMergeStrategy loopMergeStrategy = new LoopMergeStrategy(2, 0);
    
            // 从第columnIndex列开始，向右合并（columnExtend-1）列
    //        LoopMergeStrategy loopMergeStrategy = new LoopMergeStrategy(1, 2, 0);
    
            // 合并2行2列
            LoopMergeStrategy loopMergeStrategy = new LoopMergeStrategy(2, 2, 0);
    
            EasyExcel.write(fileName, WriteDemo.DemoData.class)
                    .registerWriteHandler(loopMergeStrategy)
                    .sheet("aaa")
                    .doWrite(data());
        }
    
        private List<List<Object>> data() {
        
            List<List<Object>> result = new ArrayList<>();
            for (int i = 0; i < 3; i++) {
        
                result.add(Lists.newArrayList("标题" + i, new Date(), i * 0.1));
            }
            return result;
        }
    }

分析LoopMergeStrategy类，它继承AbstractRowWriteHandler，在afterRowDispose方法里对每行做了处理，LoopMergeStrategy的构造函数传参是用来设置合并范围CellRangeAddress，再添加到当前sheet。

public void afterRowDispose(WriteSheetHolder writeSheetHolder, WriteTableHolder writeTableHolder, Row row, Integer relativeRowIndex, Boolean isHead) {
        
            if (!isHead) {
        
                if (relativeRowIndex % this.eachRow == 0) {
        
                    CellRangeAddress cellRangeAddress = new CellRangeAddress(row.getRowNum(), row.getRowNum() + this.eachRow - 1, this.columnIndex, this.columnIndex + this.columnExtend - 1);
                    writeSheetHolder.getSheet().addMergedRegionUnsafe(cellRangeAddress);
                }
    
            }
        }

CellRangeAddress构造函数有4个参数  
参数  
0：合并起始行  
1：合并终止行  
2：合并起始列  
3：合并终止列

CellRangeAddress cellRangeAddress = new CellRangeAddress(row.getRowNum(), row.getRowNum() + this.eachRow - 1, this.columnIndex, this.columnIndex + this.columnExtend - 1);
     writeSheetHolder.getSheet().addMergedRegionUnsafe(cellRangeAddress);

构造函数传进来的eachRow, columnExtend, columnIndex，都用在这里了

相关链接  
[easyexcel 动态合并单元格][easyexcel]

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[easyexcel]: https://blog.csdn.net/jianghuafeng0/article/details/110432402?utm_medium=distribute.pc_relevant.none-task-blog-BlogCommendFromMachineLearnPai2-6.control&depth_1-utm_source=distribute.pc_relevant.none-task-blog-BlogCommendFromMachineLearnPai2-6.control