EasyExcel实现三级联动

前言

项目中需要在导出的模板中新增三级联动的功能，类似省市区的联动。在网上找了一些方法，都不能直接使用，需要进行修改。本文主要分享一下，改后的代码，可以直接使用。

代码

public class CascadeWriteHandler implements SheetWriteHandler {private static char[] alphabet = new char[]{'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L','M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'};//省private List<String> provinceList;//市Map<String, List<String>> cityMap;//区Map<String, List<String>> areaMap;//省列位置private int provinceIndex;//市列位置private intcityIndex;//区列位置private int areaIndex;public CascadeWriteHandler(List<String> provinceList, Map<String, List<String>> cityMap, Map<String, List<String>> areaMap, int provinceIndex, int intcityIndex, int areaIndex) {this.provinceList= provinceList;this.cityMap= cityMap;this.areaMap= areaMap;this.provinceIndex= provinceIndex;this.intcityIndex= intcityIndex;this.areaIndex= areaIndex;}@Overridepublic void afterSheetCreate(WriteWorkbookHolder writeWorkbookHolder, WriteSheetHolder writeSheetHolder) {//获取工作簿Sheet sheet = writeSheetHolder.getSheet();Workbook book = writeWorkbookHolder.getWorkbook();//创建一个专门用来存放地区信息的隐藏sheet页//因此不能在现实页之前创建，否则无法隐藏。Sheet hideSheet = book.createSheet("site");book.setSheetHidden(book.getSheetIndex(hideSheet), true);// 将具体的数据写入到每一行中，行开头为父级区域，后面是子区域。int rowId = 0;Row proviRow = hideSheet.createRow(rowId++);proviRow.createCell(0).setCellValue("大类列表");for (int i = 0; i < provinceIndex.size(); i++) {Cell proviCell = proviRow.createCell(i + 1);proviCell.setCellValue(provinceIndex.get(i));}Iterator<String> keyIterator = cityMap.keySet().iterator();while (keyIterator.hasNext()) {String key = keyIterator.next();List<String> son = cityMap.get(key);Row row = hideSheet.createRow(rowId++);for (int i = 0; i < son.size(); i++) {Cell cell = row.createCell(i + 1);cell.setCellValue(son.get(i));}// 添加名称管理器String range = getRange(1, rowId, son.size());Name name = book.createName();name.setNameName(key);String formula = "site!" + range;name.setRefersToFormula(formula);}Iterator<String> keyIterator1 = areaMap.keySet().iterator();while (keyIterator1.hasNext()) {String key = keyIterator1.next();List<String> son = areaMap.get(key);Row row = hideSheet.createRow(rowId++);for (int i = 0; i < son.size(); i++) {Cell cell = row.createCell(i + 1);cell.setCellValue(son.get(i));}// 添加名称管理器String range = getRange(1, rowId, son.size());Name name = book.createName();name.setNameName(key);String formula = "site!" + range;name.setRefersToFormula(formula);}///开始设置（大类小类）下拉框DataValidationHelper dvHelper = sheet.getDataValidationHelper();// 大类规则DataValidationConstraint expConstraint = dvHelper.createExplicitListConstraint(industryList.toArray(new String[]{}));CellRangeAddressList expRangeAddressList = new CellRangeAddressList(1, 999, provinceIndex, provinceIndex);//todo 调整模板后位置需同步修改firstColsetValidation(sheet, dvHelper, expConstraint, expRangeAddressList, "提示", "你输入的值未在备选列表中，请下拉选择合适的值");// 小类规则(各单元格按个设置)// "INDIRECT($A$" + 2 + ")" 表示规则数据会从名称管理器中获取key与单元格 A2 值相同的数据，如果A2是浙江省，那么此处就是浙江省下面的市// 为了让每个单元格的公式能动态适应，使用循环挨个给公式。// 循环几次，就有几个单元格生效，次数要和上面的大类影响行数一一对应，要不然最后几个没对上的单元格实现不了级联for (int i = 2; i < 1000; i++) {CellRangeAddressList rangeAddressList = new CellRangeAddressList(i - 1, i - 1, intcityIndex, intcityIndex);//todo 调整模板后位置需同步修改firstColDataValidationConstraint formula = dvHelper.createFormulaListConstraint("INDIRECT($"+getExcelColumn(intcityIndex-1)+"$" + i + ")");//todo 调整模板后位置需同步修改字母setValidation(sheet, dvHelper, formula, rangeAddressList, "提示", "你输入的值未在备选列表中，请下拉选择合适的值");}for (int i = 2; i < 1000; i++) {CellRangeAddressList rangeAddressList = new CellRangeAddressList(i - 1, i - 1, areaIndex, areaIndex);//todo 调整模板后位置需同步修改firstColDataValidationConstraint formula = dvHelper.createFormulaListConstraint("INDIRECT($"+getExcelColumn(areaIndex-1)+"$" + i + ")");//todo 调整模板后位置需同步修改字母setValidation(sheet, dvHelper, formula, rangeAddressList, "提示", "你输入的值未在备选列表中，请下拉选择合适的值");}}/*** 设置验证规则** @param sheet       sheet对象* @param helper      验证助手* @param constraint  createExplicitListConstraint* @param addressList 验证位置对象* @param msgHead     错误提示头* @param msgContext  错误提示内容*/private void setValidation(Sheet sheet, DataValidationHelper helper, DataValidationConstraint constraint, CellRangeAddressList addressList, String msgHead, String msgContext) {DataValidation dataValidation = helper.createValidation(constraint, addressList);dataValidation.setErrorStyle(DataValidation.ErrorStyle.STOP);dataValidation.setShowErrorBox(true);dataValidation.setSuppressDropDownArrow(true);dataValidation.createErrorBox(msgHead, msgContext);sheet.addValidationData(dataValidation);}/*** @param offset   偏移量，如果给0，表示从A列开始，1，就是从B列* @param rowId    第几行* @param colCount 一共多少列* @return 如果给入参 1,1,10. 表示从B1-K1。最终返回 $B$1:$K$1* @author denggonghai 2016年8月31日 下午5:17:49*/public String getRange(int offset, int rowId, int colCount) {char start = (char) ('A' + offset);if (colCount <= 25) {char end = (char) (start + colCount - 1);return "$" + start + "$" + rowId + ":$" + end + "$" + rowId;} else {char endPrefix = 'A';char endSuffix = 'A';if ((colCount - 25) / 26 == 0 || colCount == 51) {// 26-51之间，包括边界（仅两次字母表计算）if ((colCount - 25) % 26 == 0) {// 边界值endSuffix = (char) ('A' + 25);} else {endSuffix = (char) ('A' + (colCount - 25) % 26 - 1);}} else {// 51以上if ((colCount - 25) % 26 == 0) {endSuffix = (char) ('A' + 25);endPrefix = (char) (endPrefix + (colCount - 25) / 26 - 1);} else {endSuffix = (char) ('A' + (colCount - 25) % 26 - 1);endPrefix = (char) (endPrefix + (colCount - 25) / 26);}}return "$" + start + "$" + rowId + ":$" + endPrefix + endSuffix + "$" + rowId;}}/*** 将数字列转化成为字母列** @param num* @author: Jesse* @date: 2023/6/27* @return: String*/private static String getExcelColumn(int num) {String column = "";int len = alphabet.length - 1;int first = num / len;int second = num % len;if (num <= len) {column = alphabet[num] + "";} else {column = alphabet[first - 1] + "";if (second == 0) {column = column + alphabet[len] + "";} else {column = column + alphabet[second - 1] + "";}}return column;}}

ExcelProjectDto 类

@ColumnWidth(22)
@HeadRowHeight(30)
public class ExcelProjectDto {/*** 项目名称*/@ExcelProperty(value = "项目名称")//表头注解private String projName;/*** 项目所在企业名称*/@ExcelProperty(value = "企业名称")private String enterpriseName;/*** 项目所在地级名称*/@ExcelProperty(value = "地市")private String area20Name;/*** 项目所在县级名称*/@ExcelProperty(value = "区县")private String area30Name;public String getProjName() {return projName;}public void setProjName(String projName) {this.projName = projName;}public String getEnterpriseName() {return enterpriseName;}public void setEnterpriseName(String enterpriseName) {this.enterpriseName = enterpriseName;}public String getArea20Name() {return area20Name;}public void setArea20Name(String area20Name) {this.area20Name = area20Name;}public String getArea30Name() {return area30Name;}public void setArea30Name(String area30Name) {this.area30Name = area30Name;}public ExcelProjectDto(String projName, String enterpriseName, String area20Name, String area30Name) {this.projName = projName;this.enterpriseName = enterpriseName;this.area20Name = area20Name;this.area30Name = area30Name;}public ExcelProjectDto() {}
}

测试

public class EasyExcelTest {public static void main(String[] args) {List<ExcelProjectDto> dataList = new ArrayList<>();/// 准备省市aqu测试数据List<String> provinceList = Arrays.asList("apro1", "apro2", "apro3");Map<String, List<String>> cityMap = new HashMap<>();cityMap.put("apro1", Arrays.asList("acity11", "acity12"));cityMap.put("apro2", Arrays.asList("acity21", "acity22"));cityMap.put("apro3", Arrays.asList("acity31", "acity32"));Map<String, List<String>> districtMap = new HashMap<>();districtMap.put("acity11", Arrays.asList("aqu111", "aqu112"));districtMap.put("acity12", Arrays.asList("aqu121", "aqu122"));districtMap.put("acity21", Arrays.asList("aqu211", "aq212"));districtMap.put("acity22", Arrays.asList("aqu221", "aqu222"));districtMap.put("acity31", Arrays.asList("aqu311", "aqu312"));districtMap.put("acity32", Arrays.asList("aqu321", "aqu322"));// 创建写入的SheetFile file = new File("D:\\data\\test.xlsx");EasyExcel.write(file).sheet("sheet1").head(ExcelProjectDto.class).registerWriteHandler(new CascadeWriteHandler11(provinceList, cityMap,districtMap,4,5,6)).doWrite(dataList);}
}