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PHP

Abe Layee
Abe Layee
8,378 Points
Posted by Abe Layee
Abe Layee
8,378 Points

php looping through two dimensional array using for loop

I am trying to loop through my array and display the user name and password for each person, but i keep getting undefined offset 

<?php
 $getUserName = $_POST['userName'];
 $getUserPassword = $_POST['pass_word'];
 //echo "user name: " .$getUserName. " <br>" . "password " . $getUserPassword;
 $array = array(
     0 => array (
          'name' => 'Ellie',
          'password'=> 'tr89ial'
     ),
     1 => array(
         'name' => 'greatGuy',
         'password'=> 'abc123'
     ),

     2 => array (
         'name' => 'blogger',
          'password' => '23seventeen23'
     )
 );
$arrayLength = count($array);
for ($i = 0; $i <=$arrayLength; $i++) {
    for ($k =0; $k<=$i; $k++) {

    }
   echo $array[$i][$k];
}
?>

4 Answers

Wes Grant
Wes Grant
4,642 Points
Wes Grant
Wes Grant
4,642 Points

In your second loop:

for ($k =0; $k<=$i; $k++) {

it does not make sense to compare $k directly to $i. You want to compare $k to the size of the $array at $i so:

for ($k = 0; $ <= count($array[$i]); $k++) {

Abe Layee
Abe Layee
8,378 Points
Abe Layee
Abe Layee
8,378 Points

i changed it but nothing is printing out on the screen

Wes Grant
Wes Grant
4,642 Points
Wes Grant
Wes Grant
4,642 Points

Oh yeah... sorry... My PHP skills are a little rusty but I got a REPL up and running and hashed this out for you...

The issue is that PHP stores arrays a little differently than most people would expect. The "echo $array[$i][$k]" doesn't work because PHP isn't storing your values with keys 0 and 1. It is storing them with keys 'name' and 'password'. The array values at keys 0 and 1 are actually undefined. PHP has a foreach loop (http://php.net/manual/en/control-structures.foreach.php) to handle arrays with non-numeric indexes:

<?php
 $getUserName = $_POST['userName'];
 $getUserPassword = $_POST['pass_word'];
 //echo "user name: " .$getUserName. " <br>" . "password " . $getUserPassword;
 $array = array(
     0 => array (
          'name' => 'Ellie',
          'password'=> 'tr89ial'
     ),
     1 => array(
         'name' => 'greatGuy',
         'password'=> 'abc123'
     ),

     2 => array (
         'name' => 'blogger',
          'password' => '23seventeen23'
     )
 );
$arrayLength = count($array);
for ($i = 0; $i < $arrayLength; $i++) {
    foreach($array[$i] as $value) {
        echo $value;
    }
}
?>