php - 解析单个值到android

Question

I try to write a simple php file, which checks, whether a mysql value exists or not.

For this, I need to parse a simple string from json to android.

e.g: when the value exists, the string is "yes" and when it doesnt exists the string is "no".

Meanwhile I have tried a lot of "solutions", but nothing works.

To do that I usually use this:

  $abfrage = "
SELECT
 Something
FROM
 somewhere
 WHERE
 This=$that"

 ;


$link = mysql_query($abfrage) OR die("Error:"+mysql_error());


while($line = mysql_fetch_assoc($link)){
 $new=$line;

  }


print(json_encode($new));

and in Android:

try
    {
        BufferedReader reader = new BufferedReader
            (new InputStreamReader(is,"utf-8"),8);
            StringBuilder sb = new StringBuilder();
            while ((line = reader.readLine()) != null)
    {
            sb.append(line + "
");
        }
            is.close();
            result = sb.toString();
        Log.e("pass 2", "connection success ");
}
    catch(Exception e)
    {
    Log.e("Fail 2", e.toString());
}     

try
    {
 System.out.println(result);


         json_data = new JSONObject(result);

         String name=(json_data.getString("something"));

     Log.e("pass 3", "connection success ");
    }
    catch(Exception e)
    {
        Log.e("result:", result.toString());


        }

    }

This works well, an the the value of the String "name" is the value of "something".

But now my question:

Is it possible to save a string in PHP and parse them to android?

This is what i got:

 $abfrage = "SELECT Something FROM somewhere WHERE This = '$that' LIMIT 1";





// Proof whether the value exists or not

$read = mysql_db_query($db, $abfrage);     
 if (mysql_num_rows($read) == 0){

$value="no";
 }
else{
$value="yes";
};

  print json_encode($value);

And in JAVA:

 HttpClient httpclient = new DefaultHttpClient(); 
 HttpPost httppost = new HttpPost("http://localhost/test.php");
 HttpResponse response = httpclient.execute(httppost);



 String str =  EntityUtils.toString(response.getEntity());
 System.out.println(""+str); //prints: yes


  if(str=="yes") System.out.println("ok"); //not called
  if(str=="no") System.out.println("nope"); //not called

Answer 1

I faced this problem months before:

The problem is, that the String str, not only contains the word "yes". It also contains different letters/symbols, which are not displayed in Android/Eclipse. So you have to manually delete these letters by simply calling substring(int start, int end)

Try this:

String str =  EntityUtils.toString(response.getEntity());


    int number= str.length(); 
    System.out.println("str-length"+number); //You will see not the length of 3 (for    yes)

    String s2= str.substring(0, 3);  //short the string
    System.out.println("String s2"+s2);

   if(s2.equals("yes"))Log.d("Titles", str);