Good evening, how can I return values from an array according to the value of a variable? I've tried this way (unsuccessfully):
The goal would be to return the desired amount (given in return GET) of elements of an array
localhost/estudo.php?retornar=5
$retornar = $_GET['retornar'];
for ($i=0; $i < $retornar ; $i++) {
$ccs = $ccs[$i];
echo $ccs;
}
First of all I do not recommend using this type of model unless it is for case study.
Second, even for study I recommend applying some logic:
inteiro , guaranteed the user to enter a valid number Initially, applying according to your code, follow the updated template;
$retornar = 5; //(int)$_GET['retornar'];
$ccs = array("1", "2"); //código novo (já que você não postou a linha referente ao array)
for($i = 0; $i < $retornar; $i++) {
echo $ccs[$i];
}
See working link
I use 0 to check if 1 was selected because the array starts at 0, so just change the repeat loop to 1
<?php
$retornar = 5; //$_GET['retornar'];
$ccs = array("1", "2");
if($retornar > count($ccs)){
die("Quantidade indisponivel");
}
if($retornar == 0){
echo $ccs[0];
}else{
for($i = 0; $i < $retornar; $i++) {
echo $ccs[$i];
}
}
See working link
This new form is not 100% related to the information, it is for you to try to do, since the topic itself has already been answered.
The correct answer is the comment of colleague ValdeirPsr. You're spoiling the array in the loop:
for ($i=0; $i < $retornar ; $i++) {
$ccs = $ccs[$i];
echo $ccs; // Na segunda iteração, a linha anterior vai falhar
}
Just change the name of the variable, or use the index already in echo :
for ($i=0; $i < $retornar ; $i++) {
$ccs2 = $ccs[$i];
echo $ccs2;
}
If it were not an exercise, but an actual application, you could use what is already ready in PHP, in a single line:
print_r( array_slice( $ccs, 0, $_GET['retornar'] );
Or even
$pedaco = array_slice( $ccs, 0, $_GET['retornar'] );
foreach ($pedaco as $key=>$value) {
echo $value;
}
See working at IDEONE
The array_slice returns an array extracted from another, determined by an offset and a length
Manual: