Java Apache poi 日期格式
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Apache poi date format
提问by Lalit Chattar
Hi i am reading csv file and getting date in 01-01-2011 but i want it in 01-Jan-2011 format when i write .xlsx file using apache poi library. my code is
嗨，我正在读取 csv 文件并在 01-01-2011 中获取日期，但是当我使用 apache poi 库编写 .xlsx 文件时，我希望它采用 01-Jan-2011 格式。我的代码是
XSSFDataFormat df = workBook.createDataFormat();
cs.setDataFormat(df.getFormat("dd-MMM-yy"));
but it is not working for me. where am i doing mistake.
但它对我不起作用。我在哪里做错了。
采纳答案by Gagravarr
Not only do you need to create a cell format, but you also need to apply it to the cell!
您不仅需要创建单元格格式，还需要将其应用于单元格！
XSSFDataFormat df = workBook.createDataFormat();
cs.setDataFormat(df.getFormat("d-mmm-yy"));
// Get / Create our cell
XSSFRow row = sheet.createRow(2);
XSSFCell cell = row.createCell(3);
// Set it to be a date
Calendar c = Calendar.getInstance();
c.set(2012,3-1,18); // Don't forget months are 0 based on Calendar
cell.setCellValue( c.getTime() );
// Style it as a date
cell.setCellStyle(cs);
Secondly, you need to be aware that Java and Excel differ slightly in how they express Date formatting rules. You should open up a copy of Excel, format a sample cell how you want, then take a note of the formatting rules needed. In your case, you'd gone for a Java style upper case M, while in Excel it's lower case (see above)
其次，您需要注意 Java 和 Excel 在表达日期格式规则的方式上略有不同。您应该打开一个 Excel 副本，按照您想要的方式设置示例单元格的格式，然后记下所需的格式设置规则。在你的情况下，你选择了 Java 风格的大写 M，而在 Excel 中它是小写（见上文）
