Android利用Get、Post 获取网络数据

首先是Get：

布局非常easy。就一个button，主要看一下MainActivity吧：

package com.francis.httpget;

import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

public class MyActivity extends Activity {

BufferedReader bufferedReader;
InputStreamReader inputStreamReader;
InputStream inputStream;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my);
findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
new AsyncTask<String,Void,Void>() {
@Override
protected Void doInBackground(String... params) {
try {
URL url = new URL(params[0]);
URLConnection connection = url.openConnection();

inputStream = connection.getInputStream();
inputStreamReader = new InputStreamReader(inputStream,"UTF-8");
bufferedReader = new BufferedReader(inputStreamReader);

String line;
while (true) {
if ((line = bufferedReader.readLine()) != null) {
System.out.println(line);
}
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
bufferedReader.close();
inputStreamReader.close();
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}

return null;
}
}.execute("http://fanyi.youdao.com/openapi.do?keyfrom=HttpGetFrancis&key=893755706&type=data&doctype=xml&version=1.1&q=这里是有道翻译API");
}
});
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.my, menu);
return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}

url为有道翻译提供的API,很方便。控制台输出如图：



接着是Post：

非常easy，这里仅仅给出提交post请求的Button的点击事件：

和Get相比有2点须要注意：

1.url与參数是分开的；

2.connection.setDoInput(true);

connection.setDoOutput(true);

connection.setRequestMethod("POST");

// Post
findViewById(R.id.button2).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
new AsyncTask<String,Void,Void>() {
@Override
protected Void doInBackground(String... params) {
try {
URL url = new URL(params[0]);
HttpURLConnection connection = (HttpURLConnection)url.openConnection();
connection.setDoInput(true);
connection.setDoOutput(true);
connection.setRequestMethod("POST");

outputStream = connection.getOutputStream();
outputStreamWriter = new OutputStreamWriter(outputStream,"UTF-8");
bufferedWriter = new BufferedWriter(outputStreamWriter);
bufferedWriter.write("keyfrom=HttpGetFrancis&key=893755706&type=data&doctype=xml&version=1.1&q=这里是有道翻译API");
bufferedWriter.flush();

inputStream = connection.getInputStream();
inputStreamReader = new InputStreamReader(inputStream,"UTF-8");
bufferedReader = new BufferedReader(inputStreamReader);

String line;
while (true) {
if ((line = bufferedReader.readLine()) != null) {
System.out.println(line);
}
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
bufferedReader.close();
inputStreamReader.close();
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}

return null;
}
}.execute("http://fanyi.youdao.com/openapi.do");
}
});