怎样实现android http-post方法实例说明

package com.hl;

import java.io.bufferedreader;
import java.io.ioexception;
import java.io.inputstream;
import java.io.inputstreamreader;
import java.util.arraylist;
import java.util.hashmap;
import java.util.iterator;
import java.util.map;
import java.util.set;

import org.apache.http.httpentity;
import org.apache.http.httpresponse;
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;

import android.app.activity;
import android.os.bundle;
import android.view.view;
import android.view.view.onclicklistener;
import android.widget.button;
import android.widget.edittext;
import android.widget.textview;

public class simplepost extends activity {
private textview show;
private edittext txt;
private button btn;

@override
public void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);
setcontentview(r.layout.main);
show = (textview)findviewbyid(r.id.show);
txt = (edittext)findviewbyid(r.id.txt);
btn = (button)findviewbyid(r.id.btn);
btn.setonclicklistener(new onclicklistener() {

@override
public void onclick(view v) {
dopost(txt.gettext().tostring());

}
});
}

private void dopost(string val){
//封装数据
map<string, string> parmas = new hashmap<string, string>();
parmas.put("name", val);

defaulthttpclient client = new defaulthttpclient();//http客户端
httppost httppost = new httppost("http://mhycoe.com/test/post.php");

arraylist<basicnamevaluepair> pairs = new arraylist<basicnamevaluepair>();
if(parmas != null){
set<string> keys = parmas.keyset();
for(iterator<string> i = keys.iterator(); i.hasnext();) {
string key = (string)i.next();
pairs.add(new basicnamevaluepair(key, parmas.get(key)));
}
}

try {
urlencodedformentity p_entity = new urlencodedformentity(pairs, "utf-8");
/*
* 将post数据放入http请求
*/
httppost.setentity(p_entity);
/*
* 发出实际的http post请求
*/
httpresponse response = client.execute(httppost);
httpentity entity = response.getentity();
inputstream content = entity.getcontent();
string returnconnection = convertstreamtostring(content);
show.settext(returnconnection);
} catch (illegalstateexception e) {
e.printstacktrace();
} catch (ioexception e) {
e.printstacktrace();
}

}

private string convertstreamtostring(inputstream is) {
bufferedreader reader = new bufferedreader(new inputstreamreader(is));
stringbuilder sb = new stringbuilder();
string line = null;
try {
while ((line = reader.readline()) != null) {
sb.append(line);
}
} catch (ioexception e) {
e.printstacktrace();
} finally {
try {
is.close();
} catch (ioexception e) {
e.printstacktrace();
}
}
return sb.tostring();
}
}