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PHP Build a Simple PHP Application Listing Inventory Items Displaying All Products

 Tony Mikel
 Tony Mikel
10,661 Points
Posted by  Tony Mikel
 Tony Mikel
10,661 Points

Assigning keys to values

When assigning a key to a value in an array, like the following.. 

<?php  
$array[0] = "value";  
$array["key"] = "value";
?>

Can you still reach the value in $array["key"] by using the index 0? I'm sure that's not very practical but I was just curious and couldn't find the answer anywhere else.

1 Answer

LaVaughn Haynes
LaVaughn Haynes
12,397 Points
LaVaughn Haynes
LaVaughn Haynes
12,397 Points

No. You can only get to $array["key"] with $array["key"]. You have to use the key as with an associative array.

<?php 

    $array[0] = "value 1";  
    $array["key"] = "value 2";

    print_r( $array );
    // Array ( [0] => value 1 [key] => value 2 )

    echo $array[0];
    // value 1

    echo $array["key"];
    // value 2

?>

If you push a new value into the array though it will pick up with the next numerical index though.

<?php

    $array[0] = "value 1";  // 0
    $array["key"] = "value 2"; // key

    // add new value to the end
    array_push($array, "value 3"); // 1

    print_r( $array );
    // Array ( [0] => value 1 [key] => value 2 [1] => value 3 )

    echo $array[1];
    // value 3
?>
LaVaughn Haynes
LaVaughn Haynes
12,397 Points
LaVaughn Haynes
LaVaughn Haynes
12,397 Points

Technically you can convert $array to a numerically indexed array and access "value 2" using a number but you would lose that relationship to "key". I didn't think that's what you were asking though.

<?php 

    $array[0] = "value 1";  
    $array["key"] = "value 2";

    // convert keys to numbers
    $newArray = array_values( $array );

    print_r( $newArray );
    // Array ( [0] => value 1 [1] => value 2 ) 

?>
 Tony Mikel
 Tony Mikel
10,661 Points
 Tony Mikel
 Tony Mikel
10,661 Points

You answered my question. Thank you!