Android文件的读写

存储文件：
FileOutputStream outStream=this.openFileOutput("zhzhg.txt",Context.MODE_PRIVATE);
outStream.write("文件的读写",getBytes());
outStream.close();
读取文件：
FileInputStream inStream=this.getContext().openFileInput("zhzhg.txt");
Log.i("FileTest",readInStream(inStream));
----------------------------------------------------------------------
使用绝对路径打开文件：
File file = new File("/data/data/cn.zhzhg.action/files/zhzhg.txt");
FileInputStream inStream = new FileInputStream(file);
Log.i("FileTest", readInStream(inStream));
注意：上面文件路径中的“cn.zhzhg.action”为应用所在包，当你在编写代码时应替换为你自己应用使用的包。
----------------------------------------------------------------------
读取文件的方：
public static String readInStream(FileInputStream inStream){
try {
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int length = -1;
while((length = inStream.read(buffer)) != -1 ){
outStream.write(buffer, 0, length);
}
outStream.close();
inStream.close();
return outStream.toString();
} catch (IOException e){
Log.i("FileTest", e.getMessage());
}
return null;
}
Activity还提供了getCacheDir()和getFilesDir()方法：
getCacheDir()方法用于获取/data/data/<package name>/cache目录
getFilesDir()方法用于获取/data/data/<package name>/files目录

将文件写入SD卡内：
获取SDCard的状态：Environment.getExtemalStorageState()
EnvironmentMEDIA_MOUNTED手机装有SDCard，并且可以进行读写
获取SDCard的目录：Environment.getExtemalStorageDirectory()
File saveFile=new File("/sdcard/zhzhg.txt");
或：File sdCardDir=new File("/sdcard");//获取SD卡目录
File saveFile-new File(sdCardDir,"zhzhg.txt");
FileOutputStream outStream = new FileOutputStream(saveFile);
outStream.write("文件的读写".getBytes());
outStream.close();
注：访问SDCard必须在AndroidManifest.xml中加入访问SDCard的权限

更多相关文章

随机推荐