Android文字圖片寫入CSV(Base64)并分享

首先，CSV逗號分隔值文件格式(Comma-Separated Values)，純文本形式，逗號分隔，一行數據不跨行。

圖片轉換成Base64字符串

public String writeBase64(String path) {       //path圖片路徑
  byte[] data = null;
  try {
    InputStream in = new FileInputStream(path);
    data = new byte[in.available()];
    in.read(data);
    in.close();
  } catch (FileNotFoundException e) {
    e.printStackTrace();
  } catch (IOException e) {
    e.printStackTrace();
  }
  return Base64.encodeToString(data, Base64.NO_WRAP);       //注意這里是Base64.NO_WRAP  
}

最后返回 Base64.encodeToString(data, Base64.NO_WRAP)， 注意 這里要使用Base64.NO_WRAP，而不是Base64.DEFAULT。default當字符串過長（RFC2045里規定了每行最多76個字符換行），自動會加入換行符，影響使用，用NO_WRAP解決。

生成和寫入CSV

public File writeCsv() {
  String path = Environment.getExternalStorageDirectory().getAbsolutePath() + "/csv/";    //CSV文件路徑
  File csv = new File(path + "KnowYourTeam.csv");
  File pa = new File(path);
  if (!pa.exists()) {
    pa.mkdirs();
  }
  if (!csv.exists()) {
    try {
      csv.createNewFile();
    } catch (IOException e) {
      e.printStackTrace();
    }
  } else {
    try {
      csv.delete();               //這里寫的如果文件存在會刪除文件新建一個文件
      csv.createNewFile();
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
  try {
    BufferedWriter bw = new BufferedWriter(new FileWriter(csv, true));
    ArrayList<Person> list = new PersonDao(this).queryAll();              //數據庫取Person List
    for (Person person : list) {                                 //循環寫入person數據(name,title,image)
      String img = writeBase64(person.getPicPath());                    //getPicPath()路徑
      bw.write(person.getName() + "," + person.getTitle() + "," + img);
      bw.newLine();                                    //換行，一行一組數據
    }
    bw.close();
  } catch (IOException e) {
    e.printStackTrace();
  }
  return csv;
}

File csv = writeCsv();
  Intent sendIntent = new Intent();
  sendIntent.setAction(Intent.ACTION_SEND);
  sendIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(csv));
  sendIntent.putExtra(Intent.EXTRA_SUBJECT, "KnowYourTeam shared data");
  SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//設置日期格式
  sendIntent.putExtra(Intent.EXTRA_TEXT, "There is CSV. " + df.format(new Date()));
  sendIntent.setType("text/comma-separated-values");
  startActivity(Intent.createChooser(sendIntent, "share"));

Intent.ACTION_SEND 帶附件發送

Intent.createChooser(sentIntent, "share") 可以選擇支持這種格式的應用打開分享