Unable to get request parameters in php

Question

I am using the following code to get data from $_REQUEST in php:

for($i=0;$i<intval($q);$i++)
    {
       $construct="'".$i."'";
       echo $construct;
       $p=$_REQUEST[$construct];
       echo $p;

    }

where '0','1',... so on have values. But for some reason it does not work. However if I replace it by $_REQUEST['0'] it seems to print the value fine. Any ideas what I am doing wrong?

Definitely sure. If i say echo $_REQUEST['0'], it prints the value. — user1667307, Oct 02 '12 at 04:20
*(related)* [What's wrong with using `$_REQUEST`](http://stackoverflow.com/questions/2142497/whats-wrong-with-using-request) — Gordon, Oct 02 '12 at 07:17

poplitea · Answer 1 · 2012-10-02T04:27:41.900

1

Remove the quotes around $i:

for($i=0;$i<intval($q);$i++)
{
   $construct=$i;
   echo $construct;
   $p=$_REQUEST[$construct];
   echo $p;

}

This is because the quotes are not part of the array indexes.

Besides, if you want to debug, you could write out the entire contents of the $_REQUEST-variable like this:

print "<pre>";
print_r($_REQUEST);
print "</pre>";

EDIT:

$a[$b] is the same whether $b=0 or $b='0' or $b="0", but not when $b="'0'".

edited Oct 02 '12 at 04:27

answered Oct 02 '12 at 04:16

poplitea

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@xdazz - you are correct, but the code in the question would actually equate to `$_REQUEST["0"] != $_REQUEST["'0'"]` or to use all single quotes `$_REQUEST['0'] != $_REQUEST['\'0\'']` – doublesharp Oct 02 '12 at 04:24
@xdazz I agree with doublesharp here. See my added line under EDIT. – poplitea Oct 02 '12 at 04:29
@poplitea Yes, that's the issue. – xdazz Oct 02 '12 at 04:44

score 1 · Accepted Answer · answered Oct 02 '12 at 04:18

Your $construct variable's value contains single quotes, which are not necessary. When you write it out as '0' you are indicating an actual value of 0, whereas "'0'" indicates a value of '0'. Your code should read:

for($i=0;$i<intval($q);$i++)
{
   $construct= strval($i);
   echo $construct;
   $p=$_REQUEST[$construct];
   echo $p;
}

or more simply:

for ($i=0; $i<intval($q); $i++) {
   echo $_REQUEST[strval($i)];
}

Unable to get request parameters in php

2 Answers2