Android 實作檔案上傳功能

檔案上傳在B/S應用中是一種十分常見的功能，那麼在Android平台下是否可以實現像B/S那樣的檔案上傳功能呢？答案是肯定的。下面是一個模擬網站程式上傳檔案的範例。這裡只寫出了Android部分的程式碼，伺服器的程式碼沒有貼出來，有需要完整上傳功能程式碼的朋友可以跟我聯絡喲…

 

先新建一個Android工程，新建主啟動Activity：

MainActivity.java：
 
package com.xzq.upload;
 
import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
 
public class MainActivity extends Activity
{
 
  private String newName = "htys.mp3";
  //要上传的本地文件路径
  private String uploadFile = "/data/data/com.xzq/htys.mp3";
  //上传到服务器的指定位置
  private String actionUrl = "http://192.168.100.100:8080/upload/upload.jsp";
  private TextView mTextView1;
  private TextView mTextView2;
  private Button mButton1;
 
  @Override
  public void onCreate(Bundle savedInstanceState)
  {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    mTextView1 = (TextView) findViewById(R.id.myText2);
    mTextView1.setText("FilePath：/n" + uploadFile);
    mTextView2 = (TextView) findViewById(R.id.myText3);
    mTextView2.setText("UploadPath：/n" + actionUrl);
    /* 设定mButton的onClick事件处理 */
    mButton1 = (Button) findViewById(R.id.myButton);
    mButton1.setOnClickListener(new View.OnClickListener()
    {
      public void onClick(View v)
      {
        uploadFile();
      }
    });
  }
 
  private void uploadFile()
  {
    String end = "/r/n";
    String Hyphens = "--";
    String boundary = "*****";
    try 
    {
      URL url = new URL(actionUrl);
      HttpURLConnection con = (HttpURLConnection) url.openConnection();
      /* 允许Input、Output，不使用Cache */
      con.setDoInput(true);
      con.setDoOutput(true);
      con.setUseCaches(false);
      /* 设定传送的method=POST */
      con.setRequestMethod("POST");
      /* setRequestProperty */
      con.setRequestProperty("Connection", "Keep-Alive");
      con.setRequestProperty("Charset", "UTF-8");
      con.setRequestProperty("Content-Type",
          "multipart/form-data;boundary=" + boundary);
      /* 设定DataOutputStream */
      DataOutputStream ds = new DataOutputStream(con.getOutputStream());
      ds.writeBytes(Hyphens + boundary + end);
      ds.writeBytes("Content-Disposition: form-data; "
          + "name=/"file1/";filename=/"" + newName + "/"" + end);
      ds.writeBytes(end);
      /* 取得文件的FileInputStream */
      FileInputStream fStream = new FileInputStream(uploadFile);
      /* 设定每次写入1024bytes */
      int bufferSize = 1024;
      byte[] buffer = new byte[bufferSize];
      int length = -1;
      /* 从文件读取数据到缓冲区 */
      while ((length = fStream.read(buffer)) != -1)
      {
        /* 将数据写入DataOutputStream中 */
        ds.write(buffer, 0, length);
      }
      ds.writeBytes(end);
      ds.writeBytes(Hyphens + boundary + Hyphens + end);
      fStream.close();
      ds.flush();
      /* 取得Response内容 */
      InputStream is = con.getInputStream();
      int ch;
      StringBuffer b = new StringBuffer();
      while ((ch = is.read()) != -1)
      {
        b.append((char) ch);
      }
      System.out.println("上传成功");
      Toast.makeText(MainActivity.this, "上传成功", Toast.LENGTH_LONG)
          .show();
      ds.close();
    } catch (Exception e)
    {
      System.out.println("上传失败" + e.getMessage());
      Toast.makeText(MainActivity.this, "上传失败" + e.getMessage(),
          Toast.LENGTH_LONG).show();
    }
  }
}

最後別忘了在AndroidManifest.xml中設定存取Internet的權限：

  <uses-permission android:name="android.permission.INTERNET" />