Loop from array not executed

Question

I am working on an android app that should create some records on a MySQL database.

This is the PHP file that receives the POST values from the app. As you may see, there are three arrays that collect specific POST. The first and second loops are working fine and executing the related guardar_post_media() function.

But the third loop is not executed and there are real values on the variables inside the third array.

May be there is something wrong that I can´t detect, may be you can.

<?php
        require_once '../mis_php_functions/funciones_basicas.php';

        if($_SERVER['REQUEST_METHOD']=='POST'){

            $val39 = $_POST['val39']; 
            $val40 = $_POST['val40']; 
            $val46 = $_POST['val46']; 
            $val48 = $_POST['val48']; 
            $val50 = $_POST['val50']; 
            $val52 = $_POST['val52']; 
            $val54 = $_POST['val54']; 
            $val56 = $_POST['val56']; 
            $val58 = $_POST['val58']; 
            $val60 = $_POST['val60']; 
            $val62 = $_POST['val62']; 
            $val64 = $_POST['val64']; 
            $val65 = $_POST['val65']; 
            $val67 = $_POST['val67']; 
            $val69 = $_POST['val69']; 
            $val71 = $_POST['val71'];
            $val73 = $_POST['val73'];
            $val75 = $_POST['val75'];
            $val77 = $_POST['val77'];
            $val79 = $_POST['val79'];
            $val81 = $_POST['val81'];
            $val82 = $_POST['val82'];
            $val83 = $_POST['val83'];
            $val84 = $_POST['val84'];
            $val85 = $_POST['val85'];
            $val86 = $_POST['val86'];
            $val87 = $_POST['val87'];
            $val88 = $_POST['val88'];
            $val89 = $_POST['val89'];
            $val100 = $_POST['val100'];
            $val101 = $_POST['val101'];
            $val102 = $_POST['val102'];
            $val103 = $_POST['val103'];
            $val104 = $_POST['val104'];
            $status = 1;



             $post = guardar_post($val40,$val39,$val100,$val102,$status,$val103);

     if ($post != false) {


            $fotos = array($val48,$val50,$val52,$val54,$val56,$val58,$val60,$val62,$val64);


        $arrayLength = count($fotos);
        echo "Numero de fotos ".$arrayLength;
        $i = 0;
        while ($i < $arrayLength)
        {


            if ($fotos[$i] == 0){

            }
            else{
                guardar_post_media(1,$fotos[$i],$val102,$val100,$post);
            }


            echo "<br />".$fotos[$i] ."<br />";
            $i++;
        }

   $videos = array($val67,$val69,$val71,$val73,$val75,$val77,$val79,$val81,$val83);


        $arrayLength2 = count($videos);
        echo "Numero de videos ".$arrayLength2;
        $i = 0;
        while ($i < $arrayLength2)
        {


            if ($videos[$i] == 0){

            }
            else{

                guardar_post_media(2,$videos[$i],$val102,$val100,$post);
            }


            echo "<br />".$videos[$i] ."<br />";
            $i++;
        }

   $youtube = array($val85,$val86,$val87,$val88,$val89);


        $arrayLength3 = count($youtube);
        echo "Numero de youtube ".$arrayLength3;
        $i = 0;
        while ($i < $arrayLength3)
        {


            if ($youtube[$i] == 0){

            }
            else{

                guardar_post_media(3,$youtube[$i],$val102,$val100,$post);
            }


            echo "<br />".$youtube[$i] ."<br />";
            $i++;
        }



            sendMessageNuevoPost($val39,$val102,$val103,$val104); // envio de push





        }
        else{
            echo 'error';
        }
    }

    ?>

Answer 1

You have:

if ($youtube[$i] == 0){

}
else {

}

But POST vars are all strings. Change to:

if ($youtube[$i] == "0"){

}
else {

}

In otherwords, an equality on a string to numerical 0 will be true in your cases. And thus your else never executes.

*** Edit. PROOF

$test1 = "filename.dat";
$test2 = "2939";
$test3 = "some useful data";
$test4 = "0";

if ($test1 == 0) {
    // Dont do anything
}
else {
    echo "Do Work 1.";
}

if ($test2 == 0) {
    // Dont do anything
}
else {
    echo "Do Work 2.";
}

if ($test3 == 0) {
    // Dont do anything
}
else {
    echo "Do Work 3.";
}

if ($test4 == 0) {
    // Dont do anything
}
else {
    echo "Do Work 4.";
}

Only echoes out Do Work 2.. All other echo()s are not run because the equality of a string to a number 0 will return true except in those cases where the string also is numerical, and then the interpreter will compare the numerical values.

As how this relates to the OP's question: It can be inferred that the OP's POST vars must contain some non-numerical data because the OP insists that the 3rd array is populated:

But the third loop is not executed and there are real values on the variables inside the third array.

I will add likely the loop is executed, but not giving the expected the results due the reasons so mentioned.

Tested on PHP 5 and 7.