problem with input->post

[eluser]taschentuch[/eluser]
hi guys i rewrite my old code with CI but i have a problem

my old code:

Code:

foreach($_POST as $k=>$v)
if($v != "uid" && $k != "uid")
if(in_array($k, $arr2))
$neu .= "$k|";
$strr = substr($neu,0,-1);

and now CI:

Code:

function setpermission()
{
$arr2 = $this->tank_auth->get_permissions_details();
foreach($this->input->post() as $k=>$v)
if($v != "uid" && $k != "uid")
if(in_array($k, $arr2))
$neu .= "$k|";

$strr = substr($neu,0,-1);
echo $strr;
}

my problem is now

foreach($this->input->post() as $k=>$v)

does not work...

A PHP Error was encountered
Severity: Warning
Message: Invalid argument supplied for foreach()
Filename: admin/User.php
Line Number: 34

A PHP Error was encountered
Severity: Notice
Message: Undefined variable: neu
Filename: admin/User.php
Line Number: 39

how can i do this ?

thx