java - 如何将自定义数据保存到文本文件？

Question

我正在开发一个有助于我自己业务的应用程序(计费应用程序)，并且我需要将数据存储在设备中。我需要特别保存到文本文件，但我不知道我必须做什么。我必须保存的数据类型:

(mydata.txt)
##
id:1
heatUsage:2123
waterUsage:45,4
##
id:2
heatUsage:4572
waterUsage:21,2
##
id:3
heatUsage:456
waterUsage:11,4
##

有人知道如何以编程方式保存此文件吗？

Answer 1

希望这对您有用。您可以格式化数据，例如:

    public String formatData(List<User> users) {

        StringBuilder stringBuilder = new StringBuilder();

        for (int i = 0; i < users.size(); i++) {
            stringBuilder.append("##\n");
            stringBuilder.append("id:" + user.getId() + "\n");
            stringBuilder.append("heatUsage:" + user.getHeatUsage() + "\n");
            stringBuilder.append("waterUsage:" + user.getWaterUsage() + "\n");
        }

        return stringBuilder.toString();
    }

并写入文件:

private void writeToFile(String data,Context context) {
    try {
        OutputStreamWriter outputStreamWriter = new OutputStreamWriter(context.openFileOutput("filename.txt", Context.MODE_PRIVATE));
        outputStreamWriter.write(data);
        outputStreamWriter.close();
    }
    catch (IOException e) {
        Log.e("Exception", "File write failed: " + e.toString());
    } 
}