php loop with variable changing simplified - php

Question

pretty sure my title needs to be fixed but anyhow, i have this loop. background info, i have 36 input "types" that need to be inserted 1 by 1. if the value has something.. set to a variable, if not set it to NULL.
MY question is, is there a loop i can perform to do this without listing 36 of these things.
using php version 5.2.17
if (!empty($_POST['type1'])){
$type1 = $_POST['type1'];
}
else
$type1 = NULL;
if (!empty($_POST['type2'])){
$type2 = $_POST['type2'];
}
else
$type2 = NULL;
if (!empty($_POST['type3'])){
$type3 = $_POST['type3'];
}
else
$type3 = NULL; // to 36...
php/html
<?php
for ($i = 1; $i < 37; $i++){
echo "Type$i:<input name='type$i' type='text' size='20' maxlength='35' /><br />";
}
?>
edit: I don't want to use an array.

Answer 1

To actually define all those variables $type1, $type2 etc, use "variable variables":
for ($i = 1; $i < 37; $i++) {
$varname = "type$i";
if (! empty($_POST[$varname])) {
$$varname = $_POST[$varname];
}
else {
$$varname = NULL;
}
}
Others suggest using an array instead (and in principle I agree), but this is an actual answer to the question.

Answer 2

Question was updated to not use an array. Will keep it here for someone looking for an answer that can use an array.
You could add the $_POST array to a predefined array of values storing the result in another array. For example:
<?php
$defaults = array(
"type1" => NULL,
"type2" => NULL,
"type3" => NULL,
"type4" => NULL
// etc
);
$_POST = array(
"type1" => 1,
"type2" => "foo"
);
$types = $_POST + $defaults;
print_r($types);
Which results in the array:
Array
(
[type1] => 1
[type2] => foo
[type3] =>
[type4] =>
...
)
Then for your html loop:
for ($i = 1; $i < 37; $i++){
echo "Type$i:<input name='" . $types["type" . $i] . "' type='text' size='20' maxlength='35' /><br />\n";
}
It is important to note that this is slightly different than using a check with empty.

Answer 3

Use an array on both the php and form inputs.
$type = array();
for ($i = 1; $i <= 36; $i++) {
if (isset($_POST['type'][$i])){
$type[$i] = $_POST['type'][$i];
}
}
HTML/PHP
<?php
for ($i = 1; $i <= 36; $i++){
echo "Type$i:<input name='type[$i]' type='text' size='20' maxlength='35' /><br />";
}
?>

Answer 4

Just an example with an array named $post.
$post = array(
'type1' => 'one',
'name' => 'test',
'type3' => 'three'
);
$matches = preg_grep ('^type[0-9]^', array_keys($post));
foreach ($matches as $val) {
$$val = $post[$val];
}
var_export($type1);

Answer 5

Use array for this
$i = 0;
$myinputs = 36;
while($i<$myinputs){
$i++;
if(empty($_POST['type'.$i.''])){
$type[$i] = $_POST['type'.$i.''];
}else{
$type[$i] = null;
}
}
print_r($type);