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我想获取保存在 mysql Db 中的图像的标题，我发现您必须通过 Json 执行此操作，现在我有一个 .php 文件：

<?php
mysql_connect("localhost","xx","xx");
mysql_select_db("xx");

$q=mysql_query("SELECT title FROM field_title");
while($e=mysql_fetch_assoc($q))
        $output[]=$e;

print(json_encode($output));

mysql_close();
?>

它输出如下：

[{"title":"titleone"},{"title":"titletwo"},{"title":"titlethree"}]

但是现在我被卡住了，我想把这些标题放在一个简单的数组列表中，但我不知道如何在输出数据和数组列表本身之间建立联系。

ArrayList<String> list = new ArrayList<String>();  
for (??) {  
    list.add(string);  
}

是否有可能以一种简单的方式做到这一点？我看过这个例子，但我似乎无法弄清楚：

http://www.helloandroid.com/tutorials/connecting-mysql-database

谢谢。

编辑

好的，我能够通过 httppost 建立连接：但是当我运行我的应用程序时，它从一开始就崩溃了......

// http post
        InputStream inputStream = null;
        String result = null;
        try {
            DefaultHttpClient   httpclient = new DefaultHttpClient(new BasicHttpParams());
        HttpPost httppost = new HttpPost("http://www.webmention.com/bosshunting.php");
        // Depends on your web service
        httppost.setHeader("Content-type", "application/json");


        HttpResponse response = httpclient.execute(httppost);           
        HttpEntity entity = response.getEntity();
        } catch (Exception e) {
            Log.e("log_tag", "Error in http connection " + e.toString());
        }
        // convert response 
        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8);
            StringBuilder sb = new StringBuilder();

            String line = null;
            while ((line = reader.readLine()) != null)
            {
                sb.append(line + "\n");
            }
            result = sb.toString();

        } catch (Exception e) {
            Log.e("log_tag", "Error converting result " + e.toString());
        }



        // parse json data
        try {
            JSONArray jArray = new JSONArray(result);
            ArrayList imageUrls = new ArrayList();
            for (int i = 0; i < jArray.length(); i++) {
                JSONObject json_data = jArray.getJSONObject(i);

                imageUrls.add(json_data.getString("url"));
            }

        } catch (JSONException e) {
            Log.e("log_tag", "Error parsing data " + e.toString());
        }

不知道我是否以正确的方式将项目添加到数组中。我猜不是？我尝试获取 titleone、titletwo、titlethree 的 arraylist imageUrls

4

2 回答 2

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你好，我在这里检查了你的 json 响应Json 是真的。我想你在这里弄错了

try {
            JSONArray jArray = new JSONArray(result);
         ArrayList imageUrls = new ArrayList(); 
         for (int i = 0; i < jArray.length(); i++)
         { JSONObject json_data = jArray.getJSONObject(i); 
            imageUrls.add(json_data.getString("title")); }
         } catch (JSONException e) 
         { Log.e("log_tag", "Error parsing data " + e.toString()); }

    }
于 2012-09-04T16:36:37.923 回答
0

看来我的输出是错误的。

由于这有效：

   List<String> list = new ArrayList<String>();
        String string1 = "https://www.link.com/file1.jpg";
        String string2 = "https://www.link.com/file2.jpg";
        list.add(string1);
        list.add(string2);
        imageUrls = (String[]) list.toArray(new String[0]);

我尝试了以下方法：

InputStream inputStream = null;
        String result = null;
        try {
            DefaultHttpClient   httpclient = new DefaultHttpClient(new BasicHttpParams());
        HttpPost httppost = new HttpPost("http://www.file.com/connect.php");
        httppost.setHeader("Content-type", "application/json");

        HttpResponse response = httpclient.execute(httppost);           
        HttpEntity entity = response.getEntity();
        } catch (Exception e) {
            Log.e("log_tag", "Error in http connection " + e.toString());
        }
        // convert response 
        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8);
            StringBuilder sb = new StringBuilder();

            String line = null;
            while ((line = reader.readLine()) != null)
            {
                sb.append(line + "\n");
            }
            result = sb.toString();

        } catch (Exception e) {
            Log.e("log_tag", "Error converting result " + e.toString());
        }

        try {
            JSONArray jArray = new JSONArray(result);
         List<String> list = new ArrayList<String>();
         for (int i = 0; i < jArray.length(); i++)
         { JSONObject json_data = jArray.getJSONObject(i); 

            list.add(json_data.getString("url"));

         } imageUrls = (String[]) list.toArray(new String[0]);
        }catch (JSONException e) 
         { Log.e("log_tag", "Error parsing data " + e.toString()); }

    }

但不幸的是，这也给出了一个错误......似乎与我上面的日志文件中的错误相同......

于 2012-09-05T07:57:39.947 回答