Json转为Excel文件导出下载
JSON转Excel导出
1. 先写界面，一个输入框，一个打印按钮，一个清空输入框按钮
我用的是layui框架，随便用啥都行
<div class="mb_l">
<div class="pager-form">
<form class="layui-form form_across" action="">
<div class="layui-form-item">
<div class="layui-inline">
<label class="layui-form-label">输入JSON：label>
<div class="layui-input-inline" style="width: 400px; height: 300px">
<textarea id="inputJSON" lay-verify="required" style="width: 400px; height: 300px"
placeholder="请以标准数组格式json字符串进行转换导出excel
把JSON字符串用 [] 括起来
如：[{"name":"熊大","年龄":"22"},{"name":"熊二","年龄":"21"}]"
autocomplete="off" class="layui-textarea">textarea>
div>
div>
<div class="layui-inline ml-xl">
<button type="button" class="layui-btn" id="createExcelByJSON">生成Excelbutton>
<button type="button" class="layui-btn" id="clearJSON">清空输入框button>
div>
div>
form>
div>
div>
//JSON 转 Excel 导出
$('#createExcelByJSON').click(function (){
exportExcelByJSON();
})
//清空输入的JSON
$('#clearJSON').click(function () {
clearJSON();
})
function exportExcelByJSON(){
let input = valueReplace($('#inputJSON').val());
let inputJson = {
"data": input
}
console.info(inputJson);
if (isJsonString($('#inputJSON').val())){
postDownLoadFile({
url: "你的地址/exportExcelByJSON",
data: inputJson
})
} else {
layer.msg('请输入正确的JSON格式数据',{icon: 5});
}
}
//判断输入的字符串是否为JSON格式
function isJsonString(str) {
try {
if (typeof JSON.parse(str) == "object") {
return true;
}
} catch(e) {
}
return false;
}
//将输入的双引号进行转义，避免字符串被误读
function valueReplace(v){
v=v.toString().replace(new RegExp('(["\"])', 'g'),""");
return v;
}
//清空输入框
function clearJSON() {
$('#inputJSON').val("")
}
2. Controller层
@Autowired
private IService service;
@PostMapping("/exportExcelByJSON")
@ResponseBody
public ResultDTO exportExcelByJSON(HttpServletRequest request, HttpServletResponse response, @RequestParam String data){
try{
String fileName = "Json转Excel导出_" + DateUtils.getCurrentTime("yyyyMMddHHmmss");
SXSSFWorkbook workbook = service.exportJsonToExcel(fileName,data);
if (workbook != null) {
fileName = fileName + ".xlsx";
FileDownloadUtils.downloadExcel(request, response, fileName, workbook);
}
} catch (Exception e) {
e.printStackTrace();
try {
if (!response.isCommitted()) {
response.setContentType("application/json;utf-8");
response.setHeader("Content-Disposition", "");
String html = FileDownloadUtils.getErrorHtml("下载失败");
response.getOutputStream().write(html.getBytes("UTF-8"));
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
return ResultDTO.success();
}
3. Service层
@Override
public SXSSFWorkbook exportJsonToExcel(String fileName, String jsonData){
List<Object> data = new ArrayList<>();
Map<String, Object> stringObjectMap = new LinkedHashMap<>();
JSONArray jsonArray = JSONArray.fromObject(jsonData);
if (jsonArray.size() > 0) {
for (int i = 0; i < jsonArray.size(); i++) {
JSONObject jsonObject = jsonArray.getJSONObject(i);
Iterator<String> it = jsonObject.keys();
while (it.hasNext()) {
String key = it.next();
stringObjectMap.put(key, jsonObject.get(key).toString());
data.add(jsonObject.get(key).toString());
}
}
}
Set<String> title = stringObjectMap.keySet();
String[] titleRows = stringObjectMap.keySet().toArray(new String[title.size()]);
SXSSFWorkbook wb = ExcelSXSSFUtil.getSxssfWorkBookByJson(titleRows, data,null);
return wb;
}
4.工具类
public static <T> SXSSFWorkbook getSxssfWorkBookByJson(String[] title, List<Object> dataByJson, SXSSFWorkbook wb) {
//1.如果SXSSFWorkbook不存在，则创建一个
if (wb == null) {
wb = new SXSSFWorkbook();
}
//2.创建指定sheetName的sheet
SXSSFSheet sheet = wb.createSheet("sheet1");
//单元格样式-居中
CellStyle style = wb.createCellStyle();
style.setAlignment(HorizontalAlignment.CENTER);
style.setVerticalAlignment(VerticalAlignment.CENTER);
style.setWrapText(true);
//表头样式
CellStyle styleTitle = wb.createCellStyle();
styleTitle.setAlignment(HorizontalAlignment.CENTER);
styleTitle.setFillPattern(FillPatternType.SOLID_FOREGROUND);
styleTitle.setFillForegroundColor(IndexedColors.TAN.getIndex());
//3.设置表头
SXSSFRow row = sheet.createRow(0);
//声明列对象
SXSSFCell cell = null;
// 自动调整列宽
sheet.trackAllColumnsForAutoSizing();
List<String> titles = new ArrayList<>(title.length);
for (int i = 0; i < title.length; i++) {
titles.add(title[i]);
cell = row.createCell(i);
cell.setCellValue(title[i]);
cell.setCellStyle(styleTitle);
}
DataFormat format = wb.createDataFormat();
//创建内容
Iterator<Object> iterator = dataByJson.iterator();
int index = 0;
while (iterator.hasNext()) {
index++;
row = sheet.createRow(index);
/*如果需要匹配*/
for (int i = 0; i < title.length; i++) {
setCellValueNew(iterator.next(), row.createCell(i), style, format);
}
}
//修改列宽
for (int i = 0; i < titles.size(); i++) {
sheet.autoSizeColumn(i);
// 解决自动设置列宽时，内容含中文时，列宽依然不足，所以，要再加宽一点。
int width = sheet.getColumnWidth(i) * 17 / 10;
// java.lang.IllegalArgumentException: The maximum column width for an individual cell is 255 characters.
int maxExcelRowWidth = 60;
if (width > maxExcelRowWidth * 256) {
width = maxExcelRowWidth * 256;
}
sheet.setColumnWidth(i, width);
}
return wb;
}
public static void downloadExcel(HttpServletRequest request, HttpServletResponse response, String fileName, SXSSFWorkbook workbook) {
//一个流两个头
//设置下载excel的头信息
FileDownloadUtils.setExcelHeadInfo(response, request, fileName);
// 写出文件
ServletOutputStream os = null;
try {
os = response.getOutputStream();
workbook.write(os);
} catch (IOException e) {
logger.error(Thread.currentThread().getStackTrace()[1].getMethodName() + "发生的异常是: ", e);
throw new RuntimeException(e);
} finally {
try {
if (os != null) {
os.flush();
os.close();
}
if (workbook != null) {
workbook.close();
}
} catch (Exception e1) {
throw new RuntimeException(e1);
}
}
}
下面是碎碎念：
好像前端有现成的接口可以直接调用，完全不用搞得像我这么麻烦，但是我前端还没入门呢……我再去研究研究前端怎么实现