Android檔案儲存體詳細完整樣本

Android檔案儲存體詳細完整樣本

MainActivity如下:

package cc.cv;import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.InputStreamReader;import java.io.OutputStreamWriter;import android.os.Bundle;import android.app.Activity;import android.content.Context;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;/** * Demo描述: * 檔案儲存體詳細樣本 *  * 可利用Context的openFileOutput()方法將資料存放區到檔案中. * 預設的儲存路徑為/data/data//files/ * 可利用Context的openFileInput()方法將資料從檔案中讀出 *  * 在Android中常用的儲存方式: * SharedPreferences,資料庫,SD卡,檔案儲存體. * 對於最後一種方式平時用的不多,現在此寫個例子 * 整理和複習一下. *  * 注意事項: * 檔案儲存體是不需要許可權的與在SD卡上進行檔案儲存體是不一樣的 */public class MainActivity extends Activity {    private Button mSaveButton;    private Button mGetButton;    private Context mContext;    private String mFileName;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);init();}private void init(){mContext=this;mFileName="testData";mSaveButton=(Button) findViewById(R.id.saveButton);mSaveButton.setOnClickListener(new ClickListenerImpl());mGetButton=(Button) findViewById(R.id.getButton);mGetButton.setOnClickListener(new ClickListenerImpl());}private class ClickListenerImpl implements OnClickListener{@Overridepublic void onClick(View view) {switch (view.getId()) {case R.id.saveButton:saveDataToFile(mContext,mFileName);break;case R.id.getButton:getDataFromFile(mContext,mFileName);break;default:break;}}}/** * 向File中儲存資料 */private void saveDataToFile(Context context,String fileName){String data="Hello,All";FileOutputStream fileOutputStream=null;OutputStreamWriter outputStreamWriter=null;BufferedWriter bufferedWriter=null;try {fileOutputStream=context.openFileOutput(fileName, Context.MODE_PRIVATE);outputStreamWriter=new OutputStreamWriter(fileOutputStream);bufferedWriter=new BufferedWriter(outputStreamWriter);bufferedWriter.write(data);} catch (Exception e) {e.printStackTrace();}finally{try {if (bufferedWriter!=null) {bufferedWriter.close();}} catch (Exception e) {e.printStackTrace();}}}/** * 從File中讀取資料 */private void getDataFromFile(Context context,String fileName){FileInputStream fileInputStream=null;InputStreamReader inputStreamReader=null;BufferedReader bufferedReader=null;StringBuilder stringBuilder=null;String line=null;try {stringBuilder=new StringBuilder();fileInputStream=context.openFileInput(fileName);inputStreamReader=new InputStreamReader(fileInputStream);bufferedReader=new BufferedReader(inputStreamReader);while((line=bufferedReader.readLine())!=null){stringBuilder.append(line);}System.out.println("--->"+stringBuilder.toString());} catch (Exception e) {e.printStackTrace();}finally{try {if (bufferedReader!=null) {bufferedReader.close();}} catch (Exception e) {e.printStackTrace();}}}}

main.xml如下: