Android网络操作（上传下载等）

Java代码 
package com.maidong.utils; 
 
import java.io.BufferedReader; 
import java.io.DataOutputStream; 
import java.io.File; 
import java.io.FileInputStream; 
import java.io.IOException; 
import java.io.InputStream; 
import java.io.InputStreamReader; 
import java.io.UnsupportedEncodingException; 
import java.net.HttpURLConnection; 
import java.net.URL; 
import java.net.URLConnection; 
import java.net.URLDecoder; 
import java.net.URLEncoder; 
import java.util.ArrayList; 
import java.util.List; 
import java.util.Map; 
 
import org.apache.http.HttpEntity; 
import org.apache.http.NameValuePair; 
import org.apache.http.client.ClientProtocolException; 
import org.apache.http.client.HttpClient; 
import org.apache.http.client.entity.UrlEncodedFormEntity; 
import org.apache.http.client.methods.HttpPost; 
import org.apache.http.impl.client.DefaultHttpClient; 
import org.apache.http.protocol.HTTP; 
 
import android.app.Activity; 
import android.content.Context; 
import android.net.ConnectivityManager; 
import android.net.NetworkInfo; 
 
public class InternetUtils { 
 
    private static final String USER_AGENT = "User-Agent"; 
 
    public static String httpPost(String url, List<NameValuePair> nameValuePairs) throws ClientProtocolException, IOException { 
        HttpClient httpclient = new DefaultHttpClient(); 
        HttpPost httpPost = new HttpPost(url); 
        // List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2); 
        // Your DATA 
        // nameValuePairs.add(new BasicNameValuePair("id", "12345")); 
        // nameValuePairs.add(new BasicNameValuePair("stringdata", 
        // "eoeAndroid.com is Cool!")); 
 
        httpPost.setHeader(USER_AGENT, "Mozilla/4.5"); 
        HttpEntity httpEntity = null; 
        try { 
            httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs, HTTP.UTF_8)); 
            httpEntity = httpclient.execute(httpPost).getEntity();