Javascript - loop through array showing some undefined

Question

I need a bit of help with a simple code that I can't get to work.

The issue is that I want to get some data from a mysql database into my javascript. I know that I need to pull it via php, I have done that and placed it in an array, that I read via json_encode, it seems to get most data that way but some return undefined.

Below the code:

php

$sql_kunder = "SELECT * FROM Kunder";
$rows_kunder = array();
$result_kunder = $conn ->query($sql_kunder);

while($row_kunder = $result_kunder->fetch_assoc())
   {

    $rows_kunder[] = $row_kunder;

    $ordre_key = $row_kunder["Kunde_id"];
    $sql_ordre = "SELECT * FROM Ordre WHERE Order_Key = $ordre_key";
    $result_ordre = $conn ->query($sql_ordre);

    While($row_ordre = $result_ordre->fetch_assoc())
        {
            $rows_kunder[] = $row_ordre;
        }

   }

$phpArray_kunder = $rows_kunder;

That should place the 2 databases into an array (and it does)

JS

<script type="text/javascript">

var JsonKunder= <?php echo json_encode($phpArray_kunder ); ?>;

console.log(JsonKunder);
for (var key in JsonKunder)
   {
    if (JsonKunder[key].Kunde_id = JsonKunder[key].Order_Key)
        {
            console.log(JsonKunder[key].Start_dato);
            console.log(JsonKunder[key].End_dato);
            console.log(JsonKunder[key].Ordre_nr);
            console.log(JsonKunder[key].Ordre_id);
            console.log(JsonKunder[key].Kunde_navn);
            console.log(JsonKunder[key].Kunde_cvr);
            console.log(JsonKunder[key].Kunde_id);
        }
   }
</script>

output

Array[6]
0: Object
Kunde_cvr: "25659191"
Kunde_id: undefined
Kunde_navn: "Karens bix"
__proto__: Object    
1: Object
End_dato: "1485561600"
Kunde_id: "1"
Order_Key: "1"
Ordre_id: "1"
Ordre_nr: "1111"
Start_dato: "1484697600"
__proto__: Object
2: Object
End_dato: "1486684800"
Kunde_id: "1"
Order_Key: "1"
Ordre_id: "2"
Ordre_nr: "1112"
Start_dato: "1485993600"
__proto__: Object
3: Object
Kunde_cvr: "65917878"
Kunde_id: undefined
Kunde_navn: "Bygmarked"
__proto__: Object
4: Object
End_dato: "1485302400"
Kunde_id: "2"
Order_Key: "2"
Ordre_id: "3"
Ordre_nr: "2222"
Start_dato: "1484870400"
__proto__: Object
5: Object
End_dato: "1487980800"
Kunde_id: "2"
Order_Key: "2"
Ordre_id: "4"
Ordre_nr: "2223"
Start_dato: "1486771200"
__proto__: Object
length: 6
__proto__: Array[0]

As you can see, there is a bit of info misplaced.

For instance, in object 0, there is a kunde_id Undefined while in object 1, there is a kunde:id = 1. Don't really know why it does that, should not be there.

Next up the for loop spitting out the console.log, it reads as follows:

1484697600 testarray.php:30 <- from ordre ( start dato ) 
1485561600 testarray.php:31 <- from ordre ( end dato ) 
1111       testarray.php:32 <- from ordre ( ordre nr ) 
1          testarray.php:33 <- from ordre ( ordre id ) 
undefined  testarray.php:34 <- Should be Kunde navn
undefined  testarray.php:35 <- should be kunde cvr 
1          testarray.php:36 <- From kunde id

And then loops that 4 times, when I only wanted it to loop twice (number of costumers in kunde database)

Now I don't know what to do, I'm quite new to js and this is probably a simple fix... but I really need some guidance from you guys.

= is for value assignment, and == (and ===) are for comparison. — Pointy
– Pointy, Commented Jan 22, 2017 at 15:25

Trung Duong · Accepted Answer · 2017-01-22 15:22:46Z

2

You could try to update if statement to

if (JsonKunder[key].Kunde_id == JsonKunder[key].Order_Key)

= is an assignment. It's not compare operator.

answered Jan 22, 2017 at 15:22

Trung Duong

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Nicolai Zoëga · Accepted Answer · 2017-01-22 21:27:23Z

0

Well that was a embarssing mistake, how ever it didn't solve my issue ( but did get me a bit closer i think )

what my issue is, is that i can't seem to get the IF to run when i expect it to run..

my new code is like this

var i = 0 /* this is to see loops */

for (var key in JsonKunder) {

    var k_id = JsonKunder[key].Kunde_id;
    var o_key = JsonKunder[key].Order_Key;

    i++

    console.log('Counts loops ' + i );
    console.log('kunde id ' + k_id );
    console.log('ordre key ' + o_key );

    if( k_id == o_key )
    {
        console.log('in if ');
    }

}

console.log('total loops ' +i );

But it never returns any thing in the if loop, so it dosn't do what i thought it would... I know i have 6 obj. in my array, 4 ordres and 2 costumers. i thought i could tell in the If loop, that when a costumer ( k_id ) matches a Orders ( o_key ) then it should return the info in the if loop X times until they k_id and o_key no longer match.

But it do not do that... so i am a noob and can't seam to sort the data in the array like i want to.

answered Jan 22, 2017 at 21:27

Nicolai Zoëga

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1 Comment

Nicolai Zoëga Over a year ago

I have after a bit of sleep and some time away .. realised my stupid mistake, that is, that the array will never get the K_id and the O_key in the same loop, i have build the array wrong form the start. Thanks for the help though with the = and == and === :) and sorry for the wasted time.

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