使用jxl修改现有的Excel

我无法使用jxl编辑现有的Excel工作表。 它总是创造一个新的。 任何人都可以帮我解决它。 请提供一个小样本代码。

Answer 1

jxl旨在提高读取效率（因为这是API的主要用途）。 为了提高性能，在读取电子表格时不解释与输出信息相关的数据（例如，诸如字体的所有格式化信息），因为在询问原始数据值时这是多余的。

但是，如果我们需要修改此电子表格，则需要使用各种写入接口的句柄，这可以使用复制方法获得。

Workbook workbook = Workbook.getWorkbook(new File("myfile.xls")); WritableWorkbook copy = Workbook.createWorkbook(new File("temp.xls"), workbook); 

这将复制已读入的信息以及执行其他处理以解释编写电子表格所必需的字段。 这种读优化策略的缺点是我们在内存中保存了两个电子表而不是一个，从而使内存需求翻倍。

但在此之后，你可以做任何你想做的事。 喜欢：

 WritableSheet sheet2 = copy.getSheet(1); WritableCell cell = sheet2.getWritableCell(1, 2); if (cell.getType() == CellType.LABEL) { Label l = (Label) cell; l.setString("modified cell"); } copy.write(); copy.close(); workbook.close(); 

注意：这直接来自Andy Khan的教程页面 。

Answer 2

我知道这是一个很老的问题，但是如果有人会遇到同样的问题，那么为了保持正确的格式（字体类型，着色等），你应该在将它转换为Label之前保存单元格格式，然后强制单元格到以前的格式。 码：

 CellFormat cfm = cell.getCellFormat(); Label l = (Label) cell; l.setString("modified cell"); cell.setCellFormat(cfm); 

Answer 3

 //there is god example of it, you can copy in ur project and check it out, to //understand how it works Workbook wk = Workbook.getWorkbook(new File("ex.xls")); // WritableWorkbook wkr = Workbook.createWorkbook(new File("modifed.xls"), wk); /* second line makes copy of wk excel file object /creates a readable spreadsheet. both are now similar and i can Modify exiting wkr spreadsheets */ //next 2 line retrieve sheet number 0 and cell (1,1) WritableSheet getsht = wkr.getSheet(0); WritableCell getcl = getsht.getWritableCell(1, 1); //making own font WritableFont ft = new WritableFont(WritableFont.ARIAL, 20 , WritableFont.BOLD, true , UnderlineStyle.SINGLE); //making Format, which uses font WritableCellFormat form = new WritableCellFormat( ft); Number nb = ( Number ) getcl ; nb.setCellFormat( form ); wkr.write(); wkr.close(); 

Answer 4

我个人使用此代码附加xls文件，如果它不存在则创建一个。
使用jxl 2.6：

  public class Excel { private String fileName = "excel_file.xls"; private String sheetName = "sheet1"; private WritableWorkbook writableWorkbook; private int rowCount; private Workbook wb; // assigns checks if file exists or not, both cases we assign it to a WritableWorkbook // object so that we can write to it. private void assignWorkBook() throws IOException, BiffException { // File f = new File(System.getProperty("user.dir") +"\\"+fileName); File inp = new File(fileName); try{ wb = Workbook.getWorkbook(inp); writableWorkbook = Workbook.createWorkbook(inp, wb); } catch (FileNotFoundException e){ writableWorkbook = Workbook.createWorkbook(inp); //Create a new one } } public int getRowCount() { return rowCount; } // this function writes a vector to an excel file, checks if there is already a sheet // with that name or not, and uses it. then we have to close the Workbook object before // we could write to the file, and then we save the file. // That is, the file is always saved after writing to it. public void writeRow(Vector playerVector) throws WriteException, IOException, BiffException { assignWorkBook(); WritableSheet excelSheet; if(writableWorkbook.getNumberOfSheets() == 0) { excelSheet = writableWorkbook.createSheet(sheetName, 0); } else { excelSheet = writableWorkbook.getSheet(sheetName); } rowCount = excelSheet.getRows(); int colCount = 0; for(String playerStat:playerVector) { Label label = new Label(colCount++, rowCount, playerStat); excelSheet.addCell(label); } if(wb != null) { wb.close(); } writableWorkbook.write(); writableWorkbook.close(); //everytime save it. } }