本文共 3141 字，大约阅读时间需要 10 分钟。
Io编程：内存卡和sd卡。字符串存入内存卡然后读出来。
activity:
package com.sxt.day06_06;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.io.UnsupportedEncodingException;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.EditText;import android.widget.Toast;public class MainActivity extends Activity { EditText met;//文本框 @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initView(); setListener(); } private void setListener() { setSaveDataClickListener(); setReadDataClickListener(); } private void setReadDataClickListener() { findViewById(R.id.btnReadData).setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { FileInputStream in =null; try { in= openFileInput("file.dat"); byte[] data=new byte[1024]; int len = in.read(data);//返回实际读取的字节数 String text=new String(data, 0, len, "utf-8"); Toast.makeText(MainActivity.this, text, 3000).show(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); }finally{ if(in!=null){ try { in.close(); } catch (IOException e) { e.printStackTrace(); } } } } }); } private void setSaveDataClickListener() { findViewById(R.id.btnSaveData).setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { FileOutputStream out = null; try { out=openFileOutput("file.dat", MODE_PRIVATE); String text=met.getText().toString(); byte[] data=text.getBytes("utf-8");//FileOutputStream时data要转换为字节数组 out.write(data); out.flush(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); }finally{ if(out!=null){ try { out.close(); } catch (IOException e) { e.printStackTrace(); } } } } }); } private void initView() { met=(EditText) findViewById(R.id.et); }} 页面
本文转自农夫山泉别墅博客园博客，原文链接：http://www.cnblogs.com/yaowen/p/4889802.html，如需转载请自行联系原作者