array blowing my mind - php

Question

$va_fields = array();
$c = 0;
$field_num = 'field-'.$c;
settype($c,"integer");
while (isset($_POST[$field_num])){
$posted_field = $_POST[$field_num];
$va_fields = array( $c => $posted_field);
echo $c.': ';
echo '$posted_field: '.$posted_field;
$c+=1;
$field_num = 'field-'.$c;
echo ' <br /> va_fields - c:'.$va_fields[$c];
echo ' <br /> ';
}
For some reason, I cannot for the life of me get the variable $posted_fields into an array.
The values of $posted_field are what I need them to be, so I'm getting the data from the post. Then I try to store them in an array, and check the array and they aren't there. What am I doing wrong?
Edit: here's my form:
<form method="post" action="<?php echo get_site_url(); ?>/wp-admin/admin-post.php">
<input type="hidden" name="action" value="cpt_field_opts" />
<!-- some inputs here ... -->
<?php wp_nonce_field( 'cpt_field_opts', '_wp_nonce' ); ?>
<input type="hidden" name="post_type" value="<?php echo $post_type; ?>">
<input type="hidden" name="origin" value="<?php echo "http://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]"; ?>" />
<?php
$c = 0;
foreach ($fields as $field){
?>
<input type="textarea" id="field-<?php echo $c; ?>" name="field-<?php echo $c; ?>" value="<?php echo $field; ?>" size="25" /></br>
<?php
$c += 1;
}
?>
<input type="submit" value="Submit" >
</form>
<form method="post" action="<?php echo get_site_url(); ?>/wp-admin/admin-post.php">
<?php wp_nonce_field( 'cpt_field_opts_new', '_wp_nonce_2' ); ?>
<input type="hidden" name="post_type" value="<?php echo $post_type; ?>" />
<input type="hidden" name="action" value="cpt_field_opts_new" />
<input type="hidden" name="origin" value="<?php echo "http://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]"; ?>" />
<input type="submit" value="New" />
</form>
Many people are telling me to rewrite the array as this line:
$va_fields[$c] = $posted_field;
Which I have done, but I also started out with that and it still wasn't working

Answer 1

If you have a bunch of values in $_POST with names like "field-0", "field-1", etc, and you're trying to get them into an array:
$c = 0;
while (isset($_POST["field-$c"])){
// This creates a new element in $va_fields with key=$c and value=$_POST["field-$c"]
$va_fields[$c] = $_POST["field-$c"];
}
var_dump($va_fields); // should show you the array you want
But really, it would be easier to just modify your form to use inputs with name=field[] instead of numbering them. Then you would already have the array in $_POST['fields'] without having to do anything.

Answer 2

It is simple just iterate the $_POST array
<?php
$va_fields = array();
$c=0;
foreach($_POST as $val){
echo '$posted_field: '. $val;
$va_fields[$c] = $val;
}
var_dump($va_fields);
?>