1 private void save() { 2         FileOutputStream fos = null; 3         String state = Environment.getExternalStorageState();// sd状态 4         if (state.equals(Environment.MEDIA_MOUNTED)) {// 判断sd卡是否可用 5             File root = Environment.getExternalStorageDirectory(); 6             File targeDir = new File(root, super.getPackageName());// 要把文件写相应在activity下 7  8             if (!targeDir.exists()) {// 判断目录是否存在 9                 targeDir.mkdir();// 创建10             }11             // String newFile=file.toString()+"/"+"user.txt";12             // IO操作13             // 流14             try {15                 // 括号里是路径16                 fos = new FileOutputStream(new File(targeDir, "userinfo.txt"));// 输出流17                 String content = name;18                 /*19                  * for(int i=0;i<content.length();i++){20                  * fos.write(content.charAt(i));//一个个字节输 }21                  */22                 byte[] data =http://www.mamicode.com/ content.getBytes();23                 fos.write(data);24 25             } catch (FileNotFoundException e) {26                 // TODO Auto-generated catch block27                 e.printStackTrace();28             } catch (IOException e) {29                 // 输入输出都会引发IO异常30                 e.printStackTrace();31             } finally {32                 // 打开流就需要关闭33                 try {34                     fos.close();35                 } catch (IOException e) {36                     // TODO Auto-generated catch block37                     e.printStackTrace();38                 }39             }40 41         }42     }

 1 private void read() { 2         FileInputStream fis = null; 3         String state = Environment.getExternalStorageState(); 4         if (state.equals(Environment.MEDIA_MOUNTED)) { 5             File root = Environment.getExternalStorageDirectory(); 6             File file = new File(root, super.getPackageName() + "/userinfo.txt"); 7             if (file.exists()) { 8                 try { 9                     fis = new FileInputStream(file);10                     int len = 0;11                     StringBuilder builder = new StringBuilder();12                     byte[] buffer = new byte[1024];13 14                     while ((len = fis.read(buffer)) != -1) {15                         builder.append(new String(buffer, 0, len));16                         // builder.append(buffer);//乱码17                     }18                     /*19                      * while((len=fis.read())!=-1){ builder.append((char)len); }20                      */21                     Toast.makeText(getApplicationContext(), builder.toString(),22                             Toast.LENGTH_SHORT).show();23                     text2.setText(builder.toString());24 25                 } catch (FileNotFoundException e) {26                     // TODO Auto-generated catch block27                     e.printStackTrace();28                     Log.i("read", e.getMessage());29                 } catch (IOException e) {30                     // TODO Auto-generated catch block31                     e.printStackTrace();32                 } finally {33                     try {34                         fis.close();35                     } catch (IOException e) {36                         // TODO Auto-generated catch block37                         e.printStackTrace();38                     }39                 }40             }41         }42     }

 1 private void copy() { 2         FileOutputStream output = null; 3         InputStream source = null; 4         String state = Environment.getExternalStorageState(); 5         if (state.equals(Environment.MEDIA_MOUNTED)) { 6             // inputstream=super.getResources().openRawResource(R.drawable.ic_launcher); 7  8             try { 9                 AssetManager manager = super.getAssets();10                 source = manager.open("image/ic_launcher.png");11                 File target = new File(12                         Environment.getExternalStorageDirectory() + "/"13                                 + super.getPackageName() + "/mycopyimg.png");14                 output = new FileOutputStream(target);15 16                 int len = 0;17                 byte[] buffer = new byte[1024];18                 while ((len = source.read(buffer)) != -1) {19                     output.write(buffer, 0, len);20                 }21             } catch (IOException e) {22                 // TODO Auto-generated catch block23                 e.printStackTrace();24                 Log.i("111", e.getMessage());25             } finally {26                 try {27                     source.close();28                     output.close();29                 } catch (IOException e) {30                     // TODO Auto-generated catch block31                     e.printStackTrace();32                 }33             }34         }35     }