这篇文章我们探讨下在Android开发中如何执行一个Post请求。
首先我们先了解下Get请求和Post请求的区别：
表单提交中get和post方式的区别有5点
1.get是从服务器上获取数据，post是向服务器传送数据。
2.get是把参数数据队列加到提交表单的ACTION属性所指的URL中，值和表单内各个字段一一对应，在URL中可以看到。post是通过HTTPpost机制，将表单内各个字段与其内容放置在HTML HEADER内一起传送到ACTION属性所指的URL地址。用户看不到这个过程。
3.对于get方式，服务器端用Request.QueryString获取变量的值，对于post方式，服务器端用Request.Form获取提交的数据。
4.get传送的数据量较小，不能大于2KB。post传送的数据量较大，一般被默认为不受限制。但理论上，IIS4中最大量为80KB，IIS5中为100KB。
5.get安全性非常低，post安全性较高。


那么接下来让我们看看在Android平台开发中如何执行一个Post请求：
Java代码
String uriAPI = "http://192.168.1.100:8080/test/test.jsp"; //这是我测试的本地,大家可以随意改
/*建立HTTPost对象*/
HttpPost httpRequest = new HttpPost(uriAPI);
/*
* NameValuePair实现请求参数的封装
*/
List <NameValuePair> params = new ArrayList <NameValuePair>();
params.add(new BasicNameValuePair("u", "沈大海"));
params.add(new BasicNameValuePair("p", "123"));
try
{
/* 添加请求参数到请求对象*/
httpRequest.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
/*发送请求并等待响应*/
HttpResponse httpResponse = new DefaultHttpClient().execute(httpRequest);
/*若状态码为200 ok*/
if(httpResponse.getStatusLine().getStatusCode() == 200)
{
/*读返回数据*/
String strResult = EntityUtils.toString(httpResponse.getEntity());
mTextView1.setText(strResult);
}
else
{
mTextView1.setText("Error Response: "+httpResponse.getStatusLine().toString());
}
}
catch (ClientProtocolException e)
{
mTextView1.setText(e.getMessage().toString());
e.printStackTrace();
}
catch (IOException e)
{
mTextView1.setText(e.getMessage().toString());
e.printStackTrace();
}
catch (Exception e)
{
mTextView1.setText(e.getMessage().toString());
e.printStackTrace();
}


那么接下来让我们看看在Android平台开发中如何执行一个Post请求：
Java代码
String uriAPI = " h t t p ://192.168.1.100:8080/test/test.jsp"; //这是我测试的本地,大家可以随意改
/*建立HTTPost对象*/
HttpPost httpRequest = new HttpPost(uriAPI);
/*
* NameValuePair实现请求参数的封装
*/
List <NameValuePair> params = new ArrayList <NameValuePair>();
params.add(new BasicNameValuePair("u", "沈大海"));
params.add(new BasicNameValuePair("p", "123"));
try
{
/* 添加请求参数到请求对象*/
httpRequest.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
/*发送请求并等待响应*/
HttpResponse httpResponse = new DefaultHttpClient().execute(httpRequest);
/*若状态码为200 ok*/
if(httpResponse.getStatusLine().getStatusCode() == 200)
{
/*读返回数据*/
String strResult = EntityUtils.toString(httpResponse.getEntity());
mTextView1.setText(strResult);
}
else
{
mTextView1.setText("Error Response: "+httpResponse.getStatusLine().toString());
}
}
catch (ClientProtocolException e)
{
mTextView1.setText(e.getMessage().toString());
e.printStackTrace();
}
catch (IOException e)
{
mTextView1.setText(e.getMessage().toString());
e.printStackTrace();
}
catch (Exception e)
{
mTextView1.setText(e.getMessage().toString());
e.printStackTrace();
}


HttpClient httpclient=new HttpClient();
HttpPost httppost=new HttpPost("http://ssssss.com/sign");
String s="";
String ss="";
List<NameValuePair> nameValuePairs=new ArrayList<NameValuePair>(1);
nameValuePairs.add(new BasicNameValuePair("content", s+",ss"+ss));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response;
response=httpclient.execute(httppost);
System.out.println(response.toString());

HttpClient httpclient=new HttpClient();
HttpPost httppost=new HttpPost("h t t p://ssssss.com/sign");
String s="";
String ss="";
List<NameValuePair> nameValuePairs=new ArrayList<NameValuePair>(1);
nameValuePairs.add(new BasicNameValuePair("content", s+",ss"+ss));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response;
response=httpclient.execute(httppost);
System.out.println(response.toString());

import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
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.message.BasicNameValuePair;
倒包有问题，会报错，唉，心情不好，等有时间吧。。。

/** * */package com.jiuchongju.util;
import java.util.ArrayList;
import java.util.List;import java.util.Map;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.protocol.HTTP;
import org.apache.http.util.EntityUtils;/** * Description:
* @version 1.0 */
public class HttpUtil{
// 创建HttpClient对象
public static HttpClient httpClient ;
public static final String BASE_URL = "h t tp://www.xxx.com/projectname/name_baidu!jsonstring";
/** * * @param url 发送请求的URL * @return 服务器响应字符串 *
@throws Exception */
public static String getRequest(String url) throws Exception {
httpClient= new DefaultHttpClient();
try{
// 创建HttpGet对象。
HttpGet get = new HttpGet(url);
// 发送GET请求
HttpResponse httpResponse = httpClient.execute(get);
// 如果服务器成功地返回响应
if (httpResponse.getStatusLine() .getStatusCode() == 200) {
// 获取服务器响应字符串
String result = EntityUtils .toString(httpResponse.getEntity());
return result;
}
}
catch(Exception e){
e.printStackTrace();
return "获取数据失败！";
}finally{
httpClient.getConnectionManager().shutdown();
}
return null;
}


/**
*
* @param url 发送请求的URL
* @param params 请求参数
* @return 服务器响应字符串
* @throws Exception
*/
public static String postRequest(String url , Map<String ,String> rawParams) {
httpClient= new DefaultHttpClient();
try{
// 创建HttpPost对象。
HttpPost post = new HttpPost(url);
// 如果传递参数个数比较多的话可以对传递的参数进行封装
List<NameValuePair> params = new ArrayList<NameValuePair>();
for(String key : rawParams.keySet()) {
//封装请求参数
params.add(new BasicNameValuePair(key , rawParams.get(key)));
}
// 设置请求参数
post.setEntity(new UrlEncodedFormEntity( params,HTTP.UTF_8));
// 发送POST请求
HttpResponse httpResponse = httpClient.execute(post);
// 如果服务器成功地返回响应
if (httpResponse.getStatusLine() .getStatusCode() == 200) {
// 获取服务器响应字符串
String result = EntityUtils .toString(httpResponse.getEntity());
return result;
}
}catch(Exception e){
e.printStackTrace();
}finally{
httpClient.getConnectionManager().shutdown();
}
return null;
}