JSONParse array nested inside of callback lost the context

Question

I'm try to parse a object from response to web service, that has the following structure:

{ "idRonda":"1",
  "puntos":{
             "p1":{"id":1,"descripcion":"punto uno","tag":"0497e1b13e0280"},
             "p2":{"id":2,"descripcion":"punto dos","tag":"0498e9b13e0280"},
             "p4":{"id":4,"descripcion":"punto cuatro","tag":"04419092432f80"},
             "p5":{"id":5,"descripcion":"punto cinco","tag":"0462f812b82a80"},
             "p3":{"id":3,"descripcion":"punto tres","tag":"046cfd92432f80"}
           }
}

So, I try to iterate over the "array" puntos, then I do the following:

//data has the response from web service
var json = JSON.parse(data);
var puntos = json.puntos; //until here it's ok

When I print the value and type of puntos :

console.log( " Puntos Object : "+ puntos );
console.log( " TypeOf : "+ Ember.typeOf(puntos) );

Output:

Puntos Object : [object Object]
TypeOf : string

My attempt:

for (var k in puntos)
{
    // I thought that k must be "p1", "p2"..., but I'm wrong 
    if (puntos.hasOwnProperty(k))
    {  
        var values = puntos[k];
        var id = values['id'];
    }
}

If I print the k value I get(I don't know what mean it):

key: 0
key: 1
.
.
.
key: 13
key: 14
key: fmt
key: w
key: loc
key: camelize
key: decamelize
key: dasherize
key: underscore
key: classify
key: capitalize
key: htmlSafe

Now how iterate over the puntos object to get id, descripcion and tag values?

UPDATE:

 var puntos = json.puntos;      
 var db = window.sqlitePlugin.openDatabase("Rondas", "1.0", "Dev", -1);
 db.transaction(function(tx)
 {

        tx.executeSql("SELECT * from Punto;", [], function(tx, res) 
        {
            if( res.rows.length === 0)
            {
                for (var k in puntos)
                {

                    if (puntos.hasOwnProperty(k))
                    {
                        var id = puntos[k].id;
                        var descripcion = puntos[k].descripcion;
                        var tag = puntos[k].tag;
                        console.log( "KEY: "+k+" ,ID: "+id + " ,DESCRIPCIÓN: "+descripcion+" ,TAG: "+tag );
                    }

                }
            }
        }
 }

The code above fail becase the object puntos lost the scope because it inside of a callback then then only solution is ensure the object context.

SOLUTION

    db.transaction(function(tx)
    {
        //ensure the object context.
        var points = puntos;
        tx.executeSql("SELECT * from Punto;", [], function(tx, res) 
        {
            if( res.rows.length === 0)
            {
                for (var k in points)
                {
                   ...
                }   
            }
        }
    }

`for (var k in puntos)` k is the "p1" , "p2" , "p3" ... try to print the data as a string before you parse it to see where is the problem — Khalid, Jul 28 '14 at 02:28

Khalid · Answer 1 · 2014-07-28T02:18:15.830

1

Using a for loop like this

for(key in puntos)
{
   var id = puntos[key].id;
   var descripcion= puntos[key].descripcion;
   var tag = puntos[key].tag;
}

edited Jul 28 '14 at 02:18

answered Jul 28 '14 at 02:13

Khalid

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Nice except you spelled description differently than in the original code. – Steve Wellens Jul 28 '14 at 02:17
@SteveWellens Thank you ! I updated it – Khalid Jul 28 '14 at 02:18
Thanks @Khalid, but not works, I get `undefined` for all values. – Cristian Jul 28 '14 at 02:22
@CristianChaparroA. it works fine for me, and the loop you posted on your question also worked fine for me ... I don't know where is the problem – Khalid Jul 28 '14 at 02:26

JSONParse array nested inside of callback lost the context

1 Answers1