How to display the elements of an array where they are arrays?

Question

I created an array in which each index stores another array - both global so that the values are not deleted. The problem is in displaying each element, when I try, PHP returns me "Notice: Array to string Conversion"

Code:

function cadastrar($nome, $raca, $cor, $tipoPelo){

    $_SESSION['array1'][] = array($nome, $raca, $cor, $tipoPelo);

    $_SESSION['array2'][] = $_SESSION['array1'];


}

function listar(){



    for($i = 0; $i < sizeof($_SESSION['array2']); $i++){
        echo $_SESSION['array2'][$i];
    }

}

With var_dump($_SESSION['array2']); displays:

  Arrayarray(3) { [0]=> array(1) { [0]=> array(4) { [0]=> string(0) "" [1]=> string(0) "" [2]=> string(0) "" [3]=> string(0) "" } } [1]=> array(2) { [0]=> array(4) { [0]=> string(0) "" [1]=> string(0) "" [2]=> string(0) "" [3]=> string(0) "" } [1]=> array(4) { [0]=> string(5) "nome1" [1]=> string(5) "raca1" [2]=> string(4) "cor1" [3]=> string(5) "tipo1" } } [2]=> array(3) { [0]=> array(4) { [0]=> string(0) "" [1]=> string(0) "" [2]=> string(0) "" [3]=> string(0) "" } [1]=> array(4) { [0]=> string(5) "nome1" [1]=> string(5) "raca1" [2]=> string(4) "cor1" [3]=> string(5) "tipo1" } [2]=> array(4) { [0]=> string(5) "nome2" [1]=> string(6) "raça2" [2]=> string(4) "cor2" [3]=> string(5) "tipo2" } } }

Answer 1

From what I understand, you want to store several records in a session. If that’s what you can do something like

function cadastrar($nome, $raca, $cor, $tipoPelo){
    // Verifica se a $_SESSION['dados_cadastro'] existe, caso nao exista, cria um array vazio, caso exista pega o valor e coloca na variabel $dados_cadastro
    $dados_cadastro = isset($_SESSION['dados_cadastro'])?$_SESSION['dados_cadastro']:[];

    // Adiciona no array $dados_cadastro os novos dados enviados
    array_push($dados_cadastro, [$nome, $raca, $cor, $tipoPelo]);

    // Atualiza a $_SESSION['dados_cadastro'] com os dados de todos os cadastros
    $_SESSION['dados_cadastro'] = $dados_cadastro;
}

function listar(){

    // Verifica se a $_SESSION['dados_cadastro'] existe, caso não, informa que nao tem dados
    if(!isset($_SESSION['dados_cadastro'])){
        echo 'Nenhum item cadastrado';
    }else{
        // Faz um loop em todos os dados em $_SESSION['dados_cadastro'] e imprime na tela
        foreach($_SESSION['dados_cadastro'] as $cadastro){
            var_dump('<pre>');
            var_dump($cadastro);
            var_dump('</pre>');
       }
    }
}

We added 3 entries in $_SESSION['dados_register']

cadastrar('nome 1', 'raca 1', 'cor 1', 'tipo_pelo 1');
cadastrar('nome 2', 'raca 2', 'cor 2', 'tipo_pelo 2');
cadastrar('nome 3', 'raca 3', 'cor 3', 'tipo_pelo 3');

When calling list, we will see everything you have in this session variable

listar();

And the way out will be

array(4) {
  [0]=>
  string(6) "nome 1"
  [1]=>
  string(6) "raca 1"
  [2]=>
  string(5) "cor 1"
  [3]=>
  string(11) "tipo_pelo 1"
}
array(4) {
  [0]=>
  string(6) "nome 2"
  [1]=>
  string(6) "raca 2"
  [2]=>
  string(5) "cor 2"
  [3]=>
  string(11) "tipo_pelo 2"
}
array(4) {
  [0]=>
  string(6) "nome 3"
  [1]=>
  string(6) "raca 3"
  [2]=>
  string(5) "cor 3"
  [3]=>
  string(11) "tipo_pelo 3"
}

Answer 2

There is a repeating structure known for iterating arrays or objects that is the foreach.
Example of how it is used:

$array = Array("maça","banana","uva");
foreach ($array as $elemento) {
    echo $elemento."<br>";
}

Exit:

maça
banana
uva

The first parameter is the array we want to traverse the second is the variable to which the value of an array element will be assigned

---

To help your problem you can do so:

foreach($array as $elemento){
    if(!is_array($elemento)){
        echo $elemento;
    } else {
        foreach($elemento as $elemento) echo $elemento;
    }
}

It will iterate inside the foreach and check with the is_array if the element is an array, if it is not it will run echo, if it is it will iterate that array.
The tip is to take a look at the PHP documentation, here’s the link to get your doubts about the Foreach

Answer 3

This is happening to you because you created an array within an array.

If you remove the [] of $_SESSION['array1'] and $_SESSION['array2'] will work properly.

Example:

function cadastrar($nome, $raca, $cor, $tipoPelo){
    $_SESSION['array1'] = array($nome, $raca, $cor, $tipoPelo);
    $_SESSION['array2'] = $_SESSION['array1'];
}

function listar(){
   cadastrar('teste','teste1','teste2','teste3');
   foreach ($_SESSION['array1'] as $value)
      echo $value . ' ';
}
listar();

Answer 4

Just put another loop inside the first:

foreach($_SESSION['array2'] as $item){
    foreach($item as $subitem){
        echo $subitem;
    }
}

I used the foreach for being simpler, but can do with the for also