文件上传在B/S应用中是一种十分常见的功能,那么在Android平台下是否可以实现像B/S那样的文件上传功能呢?答案是肯定的。下面是一个模拟网站程序上传文件的例子。
首先新建一个Android工程,新建主启动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(); } }}
最后别忘了在AndroidManifest.xml中设置访问Internet的权限:
<uses-permission android:name="android.permission.INTERNET" />
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持武林网。
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