Question

我正在尝试使用以下代码从sdcard读取文件

     f = new RandomAccessFile("/storage/sdcard0/trac.txt", "r");

但是应用程序在崩溃的同时崩溃了。我能够在SD卡中创建和编写文件，但无法读取它。我在清单中有以下权限，我将其作为系统应用程序运行：

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_LOGS" />
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW"/>
<uses-permission android:name="android.permission.WRITE_MEDIA_STORAGE"/>
<uses-permission android:name="android.permission.READ_MEDIA_STORAGE"/>
<uses-permission android:name="android.permission.ACCESS_SUPERUSER"></uses-permission>
<uses-permission android:name="android.permission.INJECT_EVENTS"></uses-permission>

Answer 1

尝试通过以下方式获取SD卡路径：

String yourpath = Environment.getExternalStorageDirectory()
                             .getAbsolutePath() + "/folderName/";

Answer 2

try {
                File myFile = new File("/sdcard/mysdfile.txt");
                FileInputStream fIn = new FileInputStream(myFile);
                BufferedReader myReader = new BufferedReader(
                        new InputStreamReader(fIn));
                String fileStr= "";
                String aBuffer = "";
                while ((fileStr= myReader.readLine()) != null) {
                    aBuffer += fileStr+ "\n";
                }
                txtData.setText(aBuffer);
                myReader.close();
                Toast.makeText(getBaseContext(),
                        "Done reading SD 'mysdfile.txt'",
                        Toast.LENGTH_SHORT).show();
            } catch (Exception e) {
                Toast.makeText(getBaseContext(), e.getMessage(),
                        Toast.LENGTH_SHORT).show();
            }

对我有帮助。更详细：

How to read a selected text file from sdcard on android

无法从Android中的SD卡读取文件

2 个答案: