excel文件转换成二进制文件

Question

大家好，请问怎么把一个二进制的文件转换成excel文件，把一个excel文件转换成二进制文件。

Answer 1

可用一般的fread,fwrite,fopen或FileCreate,FileRead,FileWrite即可。   
  先读出Excel中的内容，然后写文件。

Answer 2

excel一般是一个字段记录位置,一个字段记录长度,一个字段记录内容,把这些转换成二进制,最后一起生成一个文件即可.

Answer 3

private void insertIt() throws FileNotFoundException,java.sql.SQLException {

java.sql.Connection con = null;
java.sql.PreparedStatement pstmt = null;
String SQL = null;
        FileInputStream fin=null;
        SQL="INSERT INTO dbo.CASE_ATTACHMENT (HELPDESK_NO, SEQ_NO, FILE_NAME,FILE_CONTENT, CREATED_BY, CREATED_DATE ) VALUES (?,  ?, ?, ?, ?, ? )";
try {
            File f = new File(ContentFileName);
            fin = new FileInputStream(f);
            int len = (int)f.length();            con = getCon();

int id=1;
pstmt = con.prepareStatement(SQL);

pstmt.setString(id++, HelpdeskNO);
            SeqNO=getNextSeqNO();
            pstmt.setInt(id++, SeqNO);
pstmt.setString(id++, f.getName());
            
            pstmt.setBinaryStream(id++, fin,len);            pstmt.setString(id++, CreatedBy);

if(CreatedDate!=null)
pstmt.setTimestamp(id++, CreatedDate.getSQLTimestamp());
else
pstmt.setTimestamp(id++, null)
;


int iAffected = pstmt.executeUpdate();
//to do
commit();
setIsNew(false);
}
catch (SQLException sqle) {
try {
//if you need..
rollback();
}
catch (Exception e) {}
System.err.println("Error : " + sqle);
sqle.printStackTrace();
throw sqle;
}
finally {
try {pstmt.close();} catch (Exception e) {}
try {closeCon();} catch (Exception e) {}
            try{     fin.close();}catch(Exception e){}
        }
}此Function 是将文件"ContentFileName" 以二进制存入数据库

Answer 4

将二进制数据从数据库读出 产生excel文件                //masterObject=home.getCase(helpDeskNo);
                int seq=hr.getInt("seq");
                String fileName=hr.getString("filename");//                CaseAttachmentHome attachHome= HomeFactory.getCaseAttachmentHome(con);
//                CaseAttachment attachment=attachHome.getCaseAttachment(helpDeskNo,seq);
//                if(!attachment.getFileName().equals(fileName))return;                    java.sql.PreparedStatement pstmt = null;
                    OutputStream   fileOut=null;
                    String SQL = null;
                    Pageable rs = null;                    SQL="SELECT FILE_CONTENT FROM dbo.CASE_ATTACHMENT WHERE HELPDESK_NO=? and SEQ_NO=?  ";
                    try {
                        int id=1;
                        pstmt = con.prepareStatement(SQL);                        pstmt.setString(id++, helpDeskNo);
                        pstmt.setInt(id++, seq);                        rs = (Pageable) pstmt.executeQuery();                        if(rs.getRowsCount()==0) throw new CaseAttachmentNotFoundException(this);                        rs.first();
                        InputStream   fc   =   rs.getBinaryStream("FILE_CONTENT");
                        log.info("size="+fc.available());
                        response.reset();
                        response.setContentType("application/x-download");
                        response.addHeader(
                            "Content-Disposition",
                            "attachment; filename=" + fileName);
                        byte[] b = new byte[fc.available()];
                        int   rec   =0;
//                        OutputStream sout   =   new   FileOutputStream(fileName);
                        ServletOutputStream   sout   =   response.getOutputStream();
//                       w fc.read(b,0,b.length);
//                       w sout.write(b);
                        while ((rec =  fc.read(b)) > 0) {
                            sout.write(b,0,rec);
                        }
                        
//                       w while(fc.read(b)!=-1){
//                       w     fileOut.write(b);
//                       w }
//                        fileOut.close();
                        sout.close();
                        fc.close();
                        rs.close();//                        fileOut   =   new   FileOutputStream(fileName);
//                        byte[]   idata   =   new   byte[8000];
//
//                        response.setCharacterEncoding("utf-8");
//                        response.setContentType("application/x-download");
//                        response.addHeader("Accept-Ranges", "bytes");
//                        response.addHeader("Accept-Length", "" + fc.available());
//                        response.addHeader(
//                            "Content-Disposition",
//                            "attachment; filename=" + fileName);
//
//                        int   rec   =0;
//                        while ((rec =  fc.read(idata)) > 0) {
//                                fileOut.write(idata,0,rec);
//                            }
////                        while(fc.read(idata)!=-1){
////                        fileOut.write(idata);
////                        }
//
//                        idata   =   null;
//                        fileOut.flush();
//                        fileOut.close();
//                        fc.close();
                    }                    catch (SQLException sqle) {
                        //to do
                        System.err.println("Error : " + sqle);
                        sqle.printStackTrace();
                        throw sqle;
                    }
                    finally {
                        try {rs.close();} catch (Exception e) {}
                        try {pstmt.close();} catch (Exception e) {}
                        try {fileOut.close();} catch (Exception e) {}
            }