php connection with android project - php

Question

I am a beginner in android development. I want to connect a php file to the android app. My php code is
<?php
$con = mysqli_connect("localhost", "root", "", "invoice_db");
if(mysqli_connect_errno($con)) {
echo "Failed to connect";
}
$response["sucess"]=0;
$invoiceid = $_POST['invc'];
$response = array();
$sql = "SELECT sl_no from invoice_table where invoice_id='$invoiceid'";
$result = mysqli_query($con,$sql);
if(!empty($result)) {
$row = mysqli_fetch_array($result);
$data = $row[0];
$response["sucess"] = 1;
}
mysqli_close($con);
?>
Here 'invc' is get from httpRequest ,
JSONObject json = jsonParser.makeHttpRequest(url_check_user, "POST", params);
And my JSONParser page contains,
if (method == "POST") {
// request method is POST
// defaultHttpClient
System.out.println("Inside json parser POST condition");
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
System.out.println("Inside json parser POST condition" + params);
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
Log.d("From httpentity", httpEntity.toString());
System.out.println("ppppppppppppphhhhhhhhhhhhhhhhhhhhppppppppppp");
is = httpEntity.getContent();
}
Now I want to check , whether the parameters were passed to the php page or not. So I want to console/log cat the $invoiceid. How can it possible in Eclipse Ide?

Answer 1

If you want to print a variable inside PHP code, you can do echo $variable. However please note that PHP code will be executed on a server and not on your android device. Moreover your PHP code is vulnerable to sql injection attacks

Answer 2

You can use JSON encoding method in your php file to get a proper JSON response like this.
$response = array (
'invoiceid' => $verify_code,
);
print json_encode($response);
which will return a JSON string to your app in a format like
{"invoiceid":"null"}
which you can decode and log it like this
InputStreamReader isw = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isw);
String line = "";
StringBuffer buffer = new StringBuffer();
while ((line = br.readLine()) != null){
buffer.append(line);
}
String finalresult = buffer.toString();
JSONObject myobject = new JSONObject(finalresult);
String flag= myobject.getString("invoiceid");
log.e("mylog",flag)
so that it will be visible in your logcat file.