androi文件读写操作

废话少说，直接上代码，看不懂的地方自己去网上查，以下代码都在我本地运行正常：

新建一个FileRW的android的项目：

新建一个com.sharandroi.file包

新建一个FileService.java的具体操作类：

package com.sharandroi.file;

import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import android.content.Context;

public class FileService {
private Context context;

public FileService(Context context) {
  this.context = context;
}

public void save(String content) throws Exception {
  FileOutputStream outStream = context.openFileOutput("sharpandroid.txt",
    Context.MODE_WORLD_WRITEABLE);
  outStream.write(content.getBytes());// 写数据
  outStream.close();// 关闭输出流
}

public String read() throws Throwable{
     FileInputStream instream = context.openFileInput("sharpandroid.txt");
     byte[] data = readFile(instream);
     return new String(data);
}

public byte[] readFile(InputStream inStream) throws Throwable{
     int len = 0;
     byte[] buffer = new byte[1024];
     ByteArrayOutputStream outStream = new ByteArrayOutputStream();
     while((len = inStream.read(buffer))!=-1){
         outStream.write(buffer,0,len);
     }
     outStream.close();
     return outStream.toByteArray();
}
}


新建一个单元测试类:FileServiceTest.java

package com.sharandroi.file;

import java.io.InputStream;
import java.io.OutputStream;
import android.content.Context;
import android.test.AndroidTestCase;
import android.util.Log;

public class FileServiceTest extends AndroidTestCase {
public void testSave() throws Throwable{
  FileService fileService = new FileService(getContext());
  fileService.save("qqqqqqqqqqqqqqqqqqqqqqqqqq");
  Log.i("aaa", fileService.read());
}
}




AndroidManifest.xml配置添加权限：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.sharandroi.file" android:versionCode="1"
android:versionName="1.0">
<application android:icon="@drawable/icon" android:label="@string/app_name">
  <uses-library android:name="android.test.runner" />
  <activity android:name=".MainActivity" android:label="@string/app_name">
   <intent-filter>
    <action android:name="android.intent.action.MAIN" />
    <category android:name="android.intent.category.LAUNCHER" />
   </intent-filter>
  </activity>
</application>
<uses-sdk android:minSdkVersion="8" />
<instrumentation android:name="android.test.InstrumentationTestRunner"
  android:targetPackage="com.sharandroi.file" android:label="Tests for My App" />
</manifest>



上面的代码把需要用的包都导进来在我本地能跑起来

File Exploreer的下面看到data/data/com.sharandroi.file/下面有个sharpandroid.txt文件倒出来就可以看到内容了