php - android 如何通过选定的id获取值

Question

下面的代码android代码从mysql获取数据并显示其中通过id获取的所有值。但我想转换代码而不是获取所有数据 id 让它只获取选定的 comment_id = 3 它们只会显示 comment _id 3 的所有相关评论的值

id             comment_id                  comment
1                   1                   love this product
2                   1                   not bad
3                   2                   too expensive
4                   2                   how much
5                   2                   too old
6                   3                   not that new
7                   5                   hate it
8                   7                   go away
9                   8                   what wrong with you
10                  4                   hi
11                  7                   hi
12                  4                   helo
13                  7                   hola
14                  4                   go away
15                  6                   nice
16                  3                   bye 

这就是 Android 代码

package com.androidjson.serverupdate_androidjsoncom;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.util.ArrayList;
import java.util.List;

public class test2 extends AppCompatActivity {

    ListView StudentListView;
    ProgressBar progressBar;
    String HttpUrl = "http://192.168.0.199/edit/AllStudentData.php";
    List<String> IdList = new ArrayList<>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_show_all_students);

        StudentListView = (ListView)findViewById(R.id.listview1);

        progressBar = (ProgressBar)findViewById(R.id.progressBar);

        new GetHttpResponse(test2.this).execute();

        //Adding ListView Item click Listener.
        StudentListView.setOnItemClickListener(new AdapterView.OnItemClickListener()
        {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

                // TODO Auto-generated method stub

                Intent intent = new Intent(test2.this,ShowSingleRecordActivity.class);

                // Sending ListView clicked value using intent.
                intent.putExtra("ListViewValue", IdList.get(position).toString());

                startActivity(intent);

                //Finishing current activity after open next activity.
                finish();

            }
        });
    }

    // JSON parse class started from here.
    private class GetHttpResponse extends AsyncTask<Void, Void, Void> {
        public Context context;

        String JSonResult;

        List<Student> studentList;

        public GetHttpResponse(Context context)
        {
            this.context = context;
        }

        @Override
        protected void onPreExecute()
        {
            super.onPreExecute();
        }

        @Override
        protected Void doInBackground(Void... arg0)
        {
            // Passing HTTP URL to HttpServicesClass Class.
            HttpServicesClass httpServicesClass = new HttpServicesClass(HttpUrl);
            try
            {
                httpServicesClass.ExecutePostRequest();

                if(httpServicesClass.getResponseCode() == 200)
                {
                    JSonResult = httpServicesClass.getResponse();

                    if(JSonResult != null)
                    {
                        JSONArray jsonArray = null;

                        try {
                            jsonArray = new JSONArray(JSonResult);

                            JSONObject jsonObject;

                            Student student;

                            studentList = new ArrayList<Student>();

                            for(int i=0; i<jsonArray.length(); i++)
                            {
                                student = new Student();

                                jsonObject = jsonArray.getJSONObject(i);

                                // Adding Student Id TO IdList Array.
                                IdList.add(jsonObject.getString("id").toString());

                                //Adding Student Name.
                                student.StudentName = jsonObject.getString("name").toString();

                                studentList.add(student);

                            }
                        }
                        catch (JSONException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                    }
                }
                else
                {
                    Toast.makeText(context, httpServicesClass.getErrorMessage(), Toast.LENGTH_SHORT).show();
                }
            }
            catch (Exception e)
            {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void result)

        {
            progressBar.setVisibility(View.GONE);

            StudentListView.setVisibility(View.VISIBLE);

            ListAdapterClass adapter = new ListAdapterClass(studentList, context);

            StudentListView.setAdapter(adapter);

        }
    }
}

这是我的 php 代码

<?php

if($_SERVER['REQUEST_METHOD']=='POST'){

include_once($_SERVER['DOCUMENT_ROOT']."/config/config.php");

 $id= $_POST['id'];

// Create connection
$conn = new mysqli($host, $user, $pass, $database);

if ($conn->connect_error) {

 die("Connection failed: " . $conn->connect_error);
}

$sql = "SELECT * FROM comments where comment_id = '$id'" ;

$result = $conn->query($sql);

if ($result->num_rows >0) {


 while($row[] = $result->fetch_assoc()) {

 $tem = $row;

 $json = json_encode($tem);

 }

} else {
 echo "No Results Found.";
}
 echo $json;

$conn->close();
}
?>

Answer 1

你应该发送 id 并将其添加到你的 mysql WHERE 中。它可能有用: link