Http網路請求
阿新 • • 發佈：2019-01-21
get是從伺服器上獲取資料，post是向伺服器傳送資料
get傳送的資料量較小，不能大於2KB。post傳送的資料量較大，一般被預設為不受限制。但理論上，IIS4中最大量為80KB，IIS5中為100KB。
get安全性非常低，post安全性較高。但是執行效率卻比Post方法好。
get方式的安全性較Post方式要差些，包含機密資訊的話，建議用Post資料提交方式；
在做資料查詢時，建議用Get方式；而在做資料新增、修改或刪除時，建議用Post方式；
HTTP GET請求
package com.zhidi.httpget; import java.io.BufferedReader; import java.io.InputStreamReader; import java.net.HttpURLConnection; import java.net.URL; import java.net.URLEncoder; import android.app.Activity; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; import android.widget.Toast; public class MainActivity extends Activity { private EditText et_username; private EditText et_password; private Button bt_show; String result=""; /**get請求URL地址*/ private static final String URL=""; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); init(); bt_show.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { //android4.0後的新的特性，網路資料請求時不能放在主執行緒中。 //7、使用執行緒執行訪問伺服器，獲取返回資訊後通知主執行緒更新UI或者提示資訊。 final Handler handler = new Handler() { @Override public void handleMessage(Message msg) { if (msg.what == 1) { //8、提示讀取結果 Toast.makeText(MainActivity.this, result, Toast.LENGTH_LONG).show(); } } }; // 啟動執行緒來執行任務 new Thread() { public void run() { //請求網路 loginByGet(et_username.getText().toString(), et_password.getText().toString()); Message m = new Message(); m.what = 1; // 傳送訊息到Handler handler.sendMessage(m); } }.start(); } }); } private void init(){ et_username=(EditText)findViewById(R.id.et_username); et_password=(EditText)findViewById(R.id.et_password); bt_show=(Button)findViewById(R.id.bt_login); } /** * 請求後臺，判斷登入結果。 * @param username * @param password */ public void loginByGet(String username, String password) { try { //1、設定請求的地址。通過URLEncoder.encode(String s,"UTF-8")將字串轉換為UTF-8編碼 String strUrl = URL +"?username=" + URLEncoder.encode(username, "UTF-8") + "&password=" + URLEncoder.encode(password, "UTF-8"); //2、根據地址建立URL物件(網路訪問的url) URL url = new URL(strUrl); //3、url.openConnection()開啟網路連結 HttpURLConnection conn = (HttpURLConnection)url.openConnection(); //4、獲取響應的輸入流物件 InputStreamReader is = new InputStreamReader(conn.getInputStream()); BufferedReader bufferedReader = new BufferedReader(is); StringBuffer strBuffer = new StringBuffer(); String line = null; //5、讀取伺服器返回資訊 while ((line = bufferedReader.readLine()) != null) { strBuffer.append(line); } result = strBuffer.toString(); //6、關閉InputStream、關閉http連線 is.close(); conn.disconnect(); } catch (Exception e) { e.printStackTrace(); } } }
HTTP POST請求
package com.zhidi.httppost; import java.io.BufferedReader; import java.io.InputStreamReader; import java.io.OutputStream; import java.net.HttpURLConnection; import java.net.URL; import java.net.URLEncoder; import android.app.Activity; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; import android.widget.Toast; public class MainActivity extends Activity { private EditText et_username; private EditText et_password; private Button bt_show; String result=""; /**post請求URL地址*/ private static final String URL=""; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); init(); bt_show.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { //android4.0後的新的特性，網路資料請求時不能放在主執行緒中。 //9、使用執行緒執行訪問伺服器，獲取返回資訊後通知主執行緒更新UI或者提示資訊。 final Handler handler = new Handler() { @Override public void handleMessage(Message msg) { if (msg.what == 1) { //8、提示讀取結果 Toast.makeText(MainActivity.this, result, Toast.LENGTH_LONG).show(); } } }; // 啟動執行緒來執行任務 new Thread() { public void run() { //請求網路 loginByPost(et_username.getText().toString(), et_password.getText().toString()); Message m = new Message(); m.what = 1; // 傳送訊息到Handler handler.sendMessage(m); } }.start(); } }); } private void init(){ et_username=(EditText)findViewById(R.id.et_username); et_password=(EditText)findViewById(R.id.et_password); bt_show=(Button)findViewById(R.id.bt_login); } /** * 請求後臺，判斷登入結果。 * @param username * @param password */ public void loginByPost(String username, String password) { try { //1、根據地址建立URL物件(網路訪問的url) URL url = new URL(URL); //2、url.openConnection()開啟網路連結 HttpURLConnection conn = (HttpURLConnection)url.openConnection(); //3、設定請求的方式 conn.setRequestMethod("POST"); conn.setDoInput(true);//傳送POST請求必須設定允許輸出 conn.setDoOutput(true);//傳送POST請求必須設定允許輸入 //4、設定請求的頭 conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); conn.setRequestProperty("Charset", "utf-8"); String data = "username=" + URLEncoder.encode(username, "UTF-8") + "&password=" + URLEncoder.encode(password, "UTF-8");//傳遞的資料 conn.setRequestProperty("Content-Length",String.valueOf(data.getBytes().length)); //5、獲取輸出流 OutputStream os = conn.getOutputStream(); os.write(data.getBytes()); os.flush(); //6、獲取響應的輸入流物件 InputStreamReader is = new InputStreamReader(conn.getInputStream()); BufferedReader bufferedReader = new BufferedReader(is); StringBuffer strBuffer = new StringBuffer(); String line = null; //7、讀取伺服器返回資訊 while ((line = bufferedReader.readLine()) != null) { strBuffer.append(line); } result = strBuffer.toString(); //8、關閉InputStream、關閉http連線 is.close(); conn.disconnect(); } catch (Exception e) { e.printStackTrace(); } } }
HttpClientGet請求
package com.zhidi.httpclientget; import java.net.URLEncoder; import org.apache.http.HttpResponse; import org.apache.http.client.HttpClient; import org.apache.http.client.methods.HttpGet; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.util.EntityUtils; import android.app.Activity; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.util.Log; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; import android.widget.Toast; /** * HttpClient get * @author Administrator */ public class MainActivity extends Activity { private EditText et_username; private EditText et_password; private Button bt_show; String result=""; /**get請求URL地址*/ private static final String URL=""; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); init(); bt_show.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { //android4.0後的新的特性，網路資料請求時不能放在主執行緒中。 //7、使用執行緒執行訪問伺服器，獲取返回資訊後通知主執行緒更新UI或者提示資訊。 final Handler handler = new Handler() { @Override public void handleMessage(Message msg) { if (msg.what == 1) { //8、提示讀取結果 Toast.makeText(MainActivity.this, result, Toast.LENGTH_LONG).show(); } } }; // 啟動執行緒來執行任務 new Thread() { public void run() { //請求網路 loginByHttpClientGet(et_username.getText().toString(), et_password.getText().toString()); Message m = new Message(); m.what = 1; // 傳送訊息到Handler handler.sendMessage(m); } }.start(); } }); } private void init(){ et_username=(EditText)findViewById(R.id.et_username); et_password=(EditText)findViewById(R.id.et_password); bt_show=(Button)findViewById(R.id.bt_login); } /** * 請求後臺，判斷登入結果。 * @param username * @param password */ public void loginByHttpClientGet(String username,String password) { //1、建立 HttpClient的例項 HttpClient httpClient = new DefaultHttpClient(); try { //2、建立某種連線方法的例項，在這裡是HttpGet。 String strUrl = URL +"?username=" + URLEncoder.encode(username, "UTF-8") + "&password=" + URLEncoder.encode(password, "UTF-8"); HttpGet httpGet = new HttpGet(strUrl); //3、獲取HttpResponse例項 HttpResponse httpResp = httpClient.execute(httpGet); //4、判斷是否能夠請求成功 if(httpResp.getStatusLine().getStatusCode()==200){ //5、獲取返回的資料 result = EntityUtils.toString(httpResp.getEntity(),"UTF-8"); } else { Log.i("HttpClientGet", "HttpGet方式請求失敗"); } } catch (Exception e) { e.printStackTrace(); }finally { // 6、釋放連線。無論執行方法是否成功，都必須釋放連線 httpClient.getConnectionManager().shutdown();//釋放連結 } } }
HttpClientPost請求
package com.zhidi.httpclientpost;
import java.util.ArrayList;
import java.util.List;
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;
import org.apache.http.util.EntityUtils;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
/**
* HttpClient post
* @author Administrator
*/
public class MainActivity extends Activity {
private EditText et_username;
private EditText et_password;
private Button bt_show;
String result="";
/**post請求URL地址*/
private static final String URL="";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
bt_show.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
//android4.0後的新的特性，網路資料請求時不能放在主執行緒中。
//8、使用執行緒執行訪問伺服器，獲取返回資訊後通知主執行緒更新UI或者提示資訊。
final Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
if (msg.what == 1) {
//9、提示讀取結果
Toast.makeText(MainActivity.this, result, Toast.LENGTH_LONG).show();
}
}
};
// 啟動執行緒來執行任務
new Thread() {
public void run() {
//請求網路
loginByHttpClientPost(et_username.getText().toString(), et_password.getText().toString());
Message m = new Message();
m.what = 1;
// 傳送訊息到Handler
handler.sendMessage(m);
}
}.start();
}
});
}
private void init(){
et_username=(EditText)findViewById(R.id.et_username);
et_password=(EditText)findViewById(R.id.et_password);
bt_show=(Button)findViewById(R.id.bt_login);
}
/**
* 請求後臺，判斷登入結果。
* @param username
* @param password
*/
public void loginByHttpClientPost(String username,String password) {
//1.建立 HttpClient的例項
HttpClient httpClient = new DefaultHttpClient();
try {
//2、建立某種連線方法的例項，在這裡是HttpPost。
HttpPost httpPost = new HttpPost(URL);
//3、封裝傳遞引數的集合
List<NameValuePair> parameters = new ArrayList<NameValuePair>();
parameters.add(new BasicNameValuePair("username", username));//往這個集合中新增你要傳遞的引數
parameters.add(new BasicNameValuePair("password", password));
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(parameters, "UTF-8");//建立傳遞引數封裝 實體物件，設定傳遞引數的編碼
httpPost.setEntity(entity);//把實體物件存入到httpPost物件中
//4、呼叫HttpClient例項的execute方法來執行建立好的method例項
HttpResponse httpResp = httpClient.execute(httpPost);
//5、判斷是否能夠請求成功
if(httpResp.getStatusLine().getStatusCode()==200){
//6、獲取返回的資料
result = EntityUtils.toString(httpResp.getEntity(),"UTF-8");
} else {
Log.i("HttpClientPost", "HttpPost方式請求失敗");
}
}catch (Exception e) {
e.printStackTrace();
}finally {
// 7、釋放連線。無論執行方法是否成功，都必須釋放連線
httpClient.getConnectionManager().shutdown();//釋放連結
}
}
}