當時的引數是js裡獲取別的地方的，其實都一樣

jsp程式碼

<div id="uploadDlg" class="easyui-dialog" data-options="iconCls:'icon-upload',closed: true" style="width:300px;height:180px;padding:30px;display:none">
        <form id="excel" method="post" enctype="multipart/form-data" >
            <input  type="file"
 
 name = "file"  id="upExcel" style="width:240px">
        </form>
    </div>

js

function saveUpload() {
    var upExcel = $("#upExcel").val();//這個是個很奇怪的值，但是可以獲取想要上傳的檔案結尾
    if(upExcel == ''){
        alert("請選擇excel,再上傳");
    }else if(upExcel.lastIndexOf(".xls")<0){//可判斷以.xls和.xlsx結尾的excel
 

        alert("只能上傳Excel檔案");
    }else {
        var formData = new FormData($("#excel")[0]);//表單id
        var xhLxComb= $("#xhLxComb").combobox('getValue');
        formData.append("xhLxComb",xhLxComb);//引數
        //formData.append("file",document.getElementById("excel"));

        $.ajax({
            url: basePath + "/dataCollectServlet.do?action=uploadExcelSO2"
 
,
            type: 'POST',
            data: formData,
            async: false,
            cache: false,
            contentType: false,
            processData: false,
            success: function (data) {
                if(data == "1"){
                    $('#uploadDlg').dialog('close');//關閉補採視窗
                    $.messager.show({  //這裡其實就在在螢幕的右下角顯示一個提示框
                        title: '提示',
                        msg:  '補採成功'
                    })
                }else if(data == "0"){
                    $('#uploadDlg').dialog('close');//關閉補採視窗
                    $.messager.show({  //這裡其實就在在螢幕的右下角顯示一個提示框
                        title: '提示',
                        msg:  '補採失敗,資料可能存在問題'
                    })
                }
                $("#dg").datagrid("reload"); //重新載入資料，即:重新整理頁面
            }
        });
    }
}

Controller層

// 上傳配置
    private static final int MEMORY_THRESHOLD = 1024 * 1024 * 3; // 3MB
    private static final int MAX_FILE_SIZE = 1024 * 1024 * 40; // 40MB
    private static final int MAX_REQUEST_SIZE = 1024 * 1024 * 50; // 50MB

/**
     * 配置上傳引數
     */
    private ServletFileUpload uploadSetting() {
        // 配置上傳引數
        DiskFileItemFactory factory = new DiskFileItemFactory();
        // 設定記憶體臨界值 - 超過後將產生臨時檔案並存儲於臨時目錄中
        factory.setSizeThreshold(MEMORY_THRESHOLD);
        // 設定臨時儲存目錄
        factory.setRepository(new File(System.getProperty("java.io.tmpdir")));
        ServletFileUpload upload = new ServletFileUpload(factory);
        // 設定最大檔案上傳值
        upload.setFileSizeMax(MAX_FILE_SIZE);
        // 設定最大請求值 (包含檔案和表單資料)
        upload.setSizeMax(MAX_REQUEST_SIZE);
        return upload;
    }

    private void uploadExcelSO2(HttpServletRequest request, HttpServletResponse response) throws IOException {
        PrintWriter out = response.getWriter();
        int ret = 0;
        ServletFileUpload upload = uploadSetting();//配置上傳引數
        List<RealTimeSO2> list = new LinkedList<RealTimeSO2>();
        String xhLx = "";
        try {
            // 解析請求的內容提取檔案資料
            @SuppressWarnings("unchecked")
            List<FileItem> formItems = upload.parseRequest(request);

            if (formItems != null && formItems.size() > 0) {
                // 迭代表單資料
                for (FileItem item : formItems) {
                    // 處理不在表單中的欄位
                    if (!item.isFormField()) {
                        list = this.dataCollectService.dealUploadExcel(item);//處理上傳的excel資料，如果是file檔案就處理file
                        continue;
                    } else {
                        xhLx = item.getString("UTF-8");
                        continue;
                    }
                }
            }
        } catch (Exception ex) {
            request.setAttribute("message", "錯誤資訊: " + ex.getMessage());
        }
        if (list == null || list.isEmpty()) {
            ret = 0;
        } else {
            ret = this.dataCollectService.uploadExcel(list, xhLx);//service層處理接收的資料
        }
        out.print(ret);
        out.flush();
        out.close();
    }

service層

public List<RealTimeSO2> dealUploadExcelSO2(FileItem item) throws IOException {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm");
        Workbook wb = new HSSFWorkbook(item.getInputStream());
        Sheet sheet = wb.getSheetAt(0);
        int totalRows = sheet.getPhysicalNumberOfRows();// 得到Excel的行數
        int totalCells = 0;
        if (totalRows > 1 && sheet.getRow(1) != null) {
            totalCells = 17;
        }
        List<RealTimeSO2> list = new LinkedList<RealTimeSO2>();
        for (int r = 2; r < totalRows; r++) {
            Row row = sheet.getRow(r);
            if (row == null) {
                break;
            }
            RealTimeSO2 realTimeSO2 = new RealTimeSO2();
            // 迴圈Excel的列
            for (int c = 0; c < totalCells; c++) {
                Cell cell = row.getCell(c);
                if (c == 0) {
                    if (cell.getCellType() == HSSFCell.CELL_TYPE_NUMERIC) {
                        cell.setCellType(HSSFCell.CELL_TYPE_STRING);
                        realTimeSO2.setFacId(cell.getStringCellValue());// 廠站id
                    }
                } else if (c == 1) {
                    if (cell.getCellType() == HSSFCell.CELL_TYPE_NUMERIC) {
                        cell.setCellType(HSSFCell.CELL_TYPE_STRING);
                        realTimeSO2.setHouseId(cell.getStringCellValue());// 管道id
                    }

                } else if (c == 2) {
                    if (cell.getCellType() == HSSFCell.CELL_TYPE_STRING) {
                        cell.setCellType(HSSFCell.CELL_TYPE_STRING);
                        realTimeSO2.setFacName(cell.getStringCellValue());// 廠站名字
                    }

                }
            }
            list.add(realTimeSO2);

        }
        return list;
    }

ps：需要兩個jar包commons-io-1.4.jar和commons-fileupload-1.2.2.jar