通过调用Environment的getExternalStorageState()方法来判断外部存储的状态:
/* 查检外部存储读取与写入功能是否可用 */ public boolean isExternalStorageWritable() {String state = Environment.getExternalStorageState();if (Environment.MEDIA_MOUNTED.equals(state)) {return true;}return false; }/*查检外部存储读取功能是否可用 */ public boolean isExternalStorageReadable() {String state = Environment.getExternalStorageState();if (Environment.MEDIA_MOUNTED.equals(state) ||Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {return true;}return false; }