Android调用asp.net编写的*.ashx（一般处理程序）获取数据

<%@ WebHandler Language="C#" Class="ssjc" %>

using System;
using System.Web;
using System.Text;
using Syit.Common;
using System.Data;

public class ssjc : IHttpHandler {

//Oracle数据库连接类
OracleDM dm = new OracleDM();

public void ProcessRequest(HttpContext context)
{
context.Response.ContentType = "text/plain";
StringBuilder jsonBuilder = new StringBuilder();
jsonBuilder.Append("{\"parent\":");
jsonBuilder.Append("{\"children\":");
jsonBuilder.Append("[");
string strSQL = @"select t1.ID,t1.STCD,t1.NAME,t1.LGTD,t1.LTTD,t2.WATERLEVEL,t2.TIME from ST_CROSS_BRIDGE t1  left join
(
SELECT * FROM (SELECT ROW_NUMBER() OVER(PARTITION BY BRIDGEID ORDER BY TIME DESC ) lev,t.* from st_bridge_waterlevel t)
WHERE lev = 1 ORDER BY TIME DESC
) t2 on t1.stcd=t2.bridgeid";
DataSet ds = dm.getsql(strSQL);
foreach (DataRowView drv in ds.Tables[0].DefaultView)
{
jsonBuilder.Append("{\"id\":\"" + drv["ID"].ToString().Trim() + "\",\"depth\":\"" + (string.IsNullOrEmpty(drv["WATERLEVEL"].ToString().Trim())?"0" : drv["WATERLEVEL"].ToString().Trim()) + "\",\"name\":\"" + drv["NAME"].ToString().Trim() + "\",\"lgtd\":\"" + drv["LGTD"].ToString().Trim() + "\",\"lttd\":\"" + drv["LTTD"].ToString().Trim() + "\"},");
}
string jsonString = jsonBuilder.ToString().TrimEnd(',');
jsonString+="]}}";
context.Response.Write(jsonString);
}

public bool IsReusable
{
get
{
return true;
}
}

}

package cn.superyouth.www;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.ClientProtocolException;
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 org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.drawable.Drawable;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;

public class SYIT_SSJC extends Activity implements MKGeneralListener {

private Toast mToast;
boolean isError = false;
List<Map<String,Object>> curData = new ArrayList<Map<String, Object>>(5);				// 当前页面使用数据

protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.syit_ssjc);

// 开启线程
new Thread() {
@Override
public void run() {
try {

} catch (Exception e) {
isError = true;
System.out.println(e.toString());
}
handler.sendEmptyMessage(0);
}
}.start();
}

/**
* 用Handler来更新UI
*/
private Handler handler = new Handler() {
public void handleMessage(Message msg) {
if(isError){
//创建提示
Dialog alertDialog = new AlertDialog.Builder(SYIT_SSJC.this).
setTitle("提示").
setMessage("服务器无响应,请稍候再试!").
setIcon(R.drawable.ic_launcher).
create();
alertDialog.show();
}else{
new ReadHttpGet().execute("http://61.190.32.10/CityLowerRoadSys/ashx/ssjc.ashx");  //这里是核心代码部分
}
}
};

// * 显示Toast消息
private void showToast(String msg) {
if (mToast == null) {
mToast = Toast.makeText(this, msg, Toast.LENGTH_SHORT);
} else {
mToast.setText(msg);
mToast.setDuration(Toast.LENGTH_SHORT);
}
mToast.show();
}

class ReadHttpGet extends AsyncTask<Object, Object, Object> {
@Override
protected Object doInBackground(Object... params) {
HttpGet httpRequest = new HttpGet(params[0].toString());
try {
HttpClient httpClient = new DefaultHttpClient();
HttpResponse httpResponse = httpClient.execute(httpRequest);
if (httpResponse.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
String strResult = EntityUtils.toString(httpResponse
.getEntity());
return strResult;
} else {
return "请求出错";
}
} catch (ClientProtocolException e) {
} catch (IOException e) {
e.printStackTrace();
}
return null;
}

protected void onCancelled(Object result) {
super.onCancelled();
}

//取得的数据保存在集合List<Map<String,Object>> curData 中，然后怎么使用都可以了
@Override
protected void onPostExecute(Object result) {
super.onPostExecute(result);
try {
// 创建一个JSON对象
JSONObject jsonObject = new JSONObject(result.toString())
.getJSONObject("parent");
// 获取某个对象的JSON数组
JSONArray jsonArray = jsonObject.getJSONArray("children");
StringBuilder builder = new StringBuilder();
for (int i = 0; i < jsonArray.length(); i++) {
// 新建一个JSON对象，该对象是某个数组里的其中一个对象
JSONObject jsonObject2 = (JSONObject) jsonArray.opt(i);
Map<String, Object> map = new HashMap<String, Object>();
map.put("id", jsonObject2.getString("id"));
map.put("name", jsonObject2.getString("name"));
map.put("depth", jsonObject2.getString("depth"));
map.put("lgtd", jsonObject2.getString("lgtd"));
map.put("lttd", jsonObject2.getString("lttd"));
curData.add(map);
}

} catch (JSONException e) {
e.printStackTrace();
}
}

protected void onPreExecute() {
Toast.makeText(getApplicationContext(), "开始HTTP GET请求",
Toast.LENGTH_LONG).show();
}

protected void onProgressUpdate(Object... values) {
super.onProgressUpdate(values);
}
}
}