使用json与mysql的Android连接

Question

JSON-MYSQL连接，在我的服务器中名为'emp‘的mysql表中有两个文本字段、名称和注释。现在我想用一个额外的字段来存储图像.但我不知道how..pls的帮助..。这是我的密码。

MainActivity.java

package com.example.jparser;

import java.io.InputStream;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ByteArrayEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;
import org.json.JSONObject;

import android.annotation.TargetApi;
import android.app.Activity;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.NavUtils;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class AddnewActivity extends Activity {

    EditText name;
    EditText comments;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_addnew);
        // Show the Up button in the action bar.
        setupActionBar();

        Button save=(Button) findViewById(R.id.button1);
        save.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {

            try{
            name=(EditText) findViewById(R.id.editText1);   
            String nm=name.getText().toString();
            comments=(EditText) findViewById(R.id.editText2);   
            String com=comments.getText().toString();

            if("".equals(nm) || "".equals(com)){

            Toast.makeText(getApplicationContext(), "Empty field detected", Toast.LENGTH_SHORT).show(); 
            }
            else{

                try {
                    JSONObject json = new JSONObject();
                    json.put("name", nm);
                    json.put("comments", com);


                    HttpClient client = new DefaultHttpClient();
                    String url = "http://share88.hostzi.com/parser/json_req.php";

                    HttpPost request = new HttpPost(url);
                    request.setEntity(new ByteArrayEntity(json.toString().getBytes("UTF8")));
                    request.setHeader("json", json.toString());
                    HttpResponse response = client.execute(request);
                    HttpEntity entity = response.getEntity();

                    if (entity != null) {
                        InputStream instream = entity.getContent();


                        Toast.makeText(getApplicationContext(), "Inserted", Toast.LENGTH_SHORT).show(); 
                    }
                name.setText(null);
                comments.setText(null);    


                } catch (Throwable t) {

                    Toast.makeText(getApplicationContext(),  "Request failed: " + t.toString(), Toast.LENGTH_SHORT).show(); 
                }


            }

            }catch(Exception e){}   

            }
        });

    }

    /**
     * Set up the {@link android.app.ActionBar}, if the API is available.
     */
    @TargetApi(Build.VERSION_CODES.HONEYCOMB)
    private void setupActionBar() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            getActionBar().setDisplayHomeAsUpEnabled(true);
        }
    }

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

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case android.R.id.home:
            // This ID represents the Home or Up button. In the case of this
            // activity, the Up button is shown. Use NavUtils to allow users
            // to navigate up one level in the application structure. For
            // more details, see the Navigation pattern on Android Design:
            //
            // http://developer.android.com/design/patterns/navigation.html#up-vs-back
            //
            NavUtils.navigateUpFromSameTask(this);
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

}

activity_addnew.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".AddnewActivity" >

    <EditText
        android:id="@+id/editText1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/textView1"
        android:layout_below="@+id/textView1"
        android:layout_marginTop="16dp"
        android:ems="10"
        android:inputType="text" />

    <Button
        android:id="@+id/button1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/editText2"
        android:layout_marginTop="48dp"
        android:text="@string/addnewcontent" />

    <EditText
        android:id="@+id/editText2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/textView2"
        android:layout_marginTop="17dp"
        android:ems="10"
        android:inputType="textPostalAddress" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/editText2"
        android:layout_below="@+id/editText1"
        android:layout_marginTop="48dp"
        android:text="@string/addcomments" />

    <TextView
        android:id="@+id/textView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_marginTop="30dp"
        android:text="@string/addname" />

</RelativeLayout>

AddnewActivity.java

package com.example.jparser;

import java.io.InputStream;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ByteArrayEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;
import org.json.JSONObject;

import android.annotation.TargetApi;
import android.app.Activity;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.NavUtils;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class AddnewActivity extends Activity {

    EditText name;
    EditText comments;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_addnew);
        // Show the Up button in the action bar.
        setupActionBar();

        Button save=(Button) findViewById(R.id.button1);
        save.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {

            try{
            name=(EditText) findViewById(R.id.editText1);   
            String nm=name.getText().toString();
            comments=(EditText) findViewById(R.id.editText2);   
            String com=comments.getText().toString();

            if("".equals(nm) || "".equals(com)){

            Toast.makeText(getApplicationContext(), "Empty field detected", Toast.LENGTH_SHORT).show(); 
            }
            else{

                try {
                    JSONObject json = new JSONObject();
                    json.put("name", nm);
                    json.put("comments", com);


                    HttpClient client = new DefaultHttpClient();
                    String url = "http://share88.hostzi.com/parser/json_req.php";

                    HttpPost request = new HttpPost(url);
                    request.setEntity(new ByteArrayEntity(json.toString().getBytes("UTF8")));
                    request.setHeader("json", json.toString());
                    HttpResponse response = client.execute(request);
                    HttpEntity entity = response.getEntity();

                    if (entity != null) {
                        InputStream instream = entity.getContent();


                        Toast.makeText(getApplicationContext(), "Inserted", Toast.LENGTH_SHORT).show(); 
                    }
                name.setText(null);
                comments.setText(null);    


                } catch (Throwable t) {

                    Toast.makeText(getApplicationContext(),  "Request failed: " + t.toString(), Toast.LENGTH_SHORT).show(); 
                }


            }

            }catch(Exception e){}   

            }
        });

    }

    /**
     * Set up the {@link android.app.ActionBar}, if the API is available.
     */
    @TargetApi(Build.VERSION_CODES.HONEYCOMB)
    private void setupActionBar() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            getActionBar().setDisplayHomeAsUpEnabled(true);
        }
    }

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

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case android.R.id.home:
            // This ID represents the Home or Up button. In the case of this
            // activity, the Up button is shown. Use NavUtils to allow users
            // to navigate up one level in the application structure. For
            // more details, see the Navigation pattern on Android Design:
            //
            // http://developer.android.com/design/patterns/navigation.html#up-vs-back
            //
            NavUtils.navigateUpFromSameTask(this);
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

}

我的PHP文件是

json_res.php

<?php

include "connect.php";

$result=mysql_query("SELECT* FROM emp");

while($row=mysql_fetch_assoc($result)){
    $output[]=$row;
    }

    print(json_encode($output));
    mysql_close();

?>

和json_req.php

<?php
$json = file_get_contents('php://input');
$obj = json_decode($json);

include "connect.php";


mysql_query("INSERT INTO emp VALUES ('','".$obj->{'name'}."', '".$obj->{'comments'}."')");
mysql_close($con);

?>

Answer 1

遵循从Android发送图像到服务器的步骤

如果要通过JSON发送图像，则需要将其转换为string，因为JSON不直接传输image

Android

步骤1：使用将图像编码为字符串的Base64将图像转换为字符串

步骤2：在JSON中传递转换后的字符串。

JSONObject json = new JSONObject(); 
json.put("name", nm);
json.put("comments", com);
json.put("image",convertedString);

服务器端的

步骤1接收JSON字符串。($yourimageString)

步骤2使用base64_decode ($yourimageString)方法将JSON字符串解码为图像。

步骤3现在将其写入文件中。你现在可以得到你的形象了。

希望能帮上忙。