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

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