variable concat using another variable to create it

[vhogarth]

hey guys, i'm getting an error with the following bit of code:

$roomname=array();
$total = sizeof($_POST['ID']);


$roomname=array("WTC_AREA1", "WTC_AREA2", "WTC_AREA3", "WTC_FCM_IBGLAB", "WTC_FCM_COMP_RM",
"WTC_FCM_COMP_RM_RESTRICTED", "WTC_QUAD1", "WTC_QUAD3", "WTC_QUAD4A", "WTC_QUAD4B", "WTC_QUAD4C",
"WTC_SUITE205");

for( $i = 0; $i < $total; $i++ )
{
$ID= $_POST['ID'][$i];
$mgr_ID=$_POST['mgr_ID'][$i];
$WTC_AREA1=$_POST['WTC_AREA1'][$i];
$WTC_AREA2=$_POST['WTC_AREA2'][$i];
$WTC_AREA3=$_POST['WTC_AREA3'][$i];
$WTC_FCM_IBGLAB=$_POST['WTC_FCM_IBGLAB'][$i];
$WTC_FCM_COMP_RM=$_POST['WTC_FCM_COMP_RM'][$i];
$WTC_FCM_COMP_RM_RESTRICTED=$_POST['WTC_FCM_COMP_RM_RESTRICTED'][$i];
$WTC_QUAD1=$_POST['WTC_QUAD1'][$i];
$WTC_QUAD3=$_POST['WTC_QUAD3'][$i];
$WTC_QUAD4A=$_POST['WTC_QUAD4A'][$i];
$WTC_QUAD4B=$_POST['WTC_QUAD4B'][$i];
$WTC_QUAD4C=$_POST['WTC_QUAD4C'][$i];
$WTC_SUITE205=$_POST['WTC_SUITE205'][$i];


$total_rooms=sizof($roomname);


$change_sql=mysql_query('SELECT ID, WTC_AREA1,
WTC_AREA2,
WTC_AREA3,
WTC_FCM_IBGLAB,
WTC_FCM_COMP_RM,
WTC_FCM_COMP_RM_RESTRICTED,
WTC_QUAD1,
WTC_QUAD3,
WTC_QUAD4A,
WTC_QUAD4B,
WTC_QUAD4C,
WTC_SUITE205
FROM access_list WHERE ID="'. $ID .'"');

while ($change_check=mysql_fetch_array($change_sql)) {


for ($n=0; $n < $total_rooms; $n++){

$rname=$roomname[$n];

//This is where the problem lies.. i'm trying to use the value of $rname to
//be the value of the new variable
$.$rname._check=$change_check['.$rname.'];


//The following conditionals checks to see if there is a difference between what was submitted in the form
//and what currently is in the DB.  The change is recorded as a new variable update.

if ($.$rname == $.$rname_check) {
$.$rname_update=0;
}else{
$.$rname_update=1;
}

//END OF FOR LOOP
} 

[krayziepjf]

Isn't the function sizeof() instead of sizof() when checking an array length? Just something I saw in the code.

[krayziepjf]

For your variable variable question, would this work for you:

$newvarname = $rname . "_check";
$$newvarname = $change_check[$rname];

//if $rname is "west", this will create a variable named $west 

[Bil]

[edit: And yeah, what krayzie said. Much better way to do it.]

My hunch is that this:

$change_check['.$rname.']

is not doing what you expect because you have $rname in single quotes, so when the program runs it is literally getting $change_check['.$rname.'] and not $change_check['WTC_Area1']. Try using just $change_check[$rname]

What's more, I don't think you need to use (.) for variable variable names. ${$rname}_check should work. (Not 100% sure about the brackets, but give it a whirl).

[vhogarth]

For your variable variable question, would this work for you:

$newvarname = $rname . "_check";
$$newvarname = $change_check[$rname];

//if $rname is "west", this will create a variable named $west 

Worked like a charm. I also fixed the sizof, i was getting too many other errors before it even noticed that one.