功能在不同环境中表现不同

Environment 1: Working PHP(5.2.4) MySQL(5.1.30)
Environment 2: Not Working PHP(5.2.6) MySQL(4.1.25-log)

What is it about this function that makes it work in environment 1, and not in environment 2? No errors, just not returning anything.

function GetPrice($type, $level){
    $result = mysql_query("SELECT * FROM `types` WHERE id = '$type'") or trigger_error(mysql_error()); 
    while($row = mysql_fetch_array($result)){ 
        foreach($row AS $key => $value) { $row[$key] = stripslashes($value); } 
            $reg = $row['regprice'];
            $nat = $row['natprice'];
    }

    if($level == "reg"){return $reg;}
    if($level == "nat"){return $nat;}

}

I figure it has something to do with the end there, where im comparing $level to the strings, but i dont know what it should be to work.

You are doing a SELECT without an ORDER BY clause, therefore you cannot expect a deterministic order of rows returned.

In practice it is very difficult to make a working application against different versions of MySQL; 4.1 is very old, consider upgrading as soon as possible.

Supporting different versions of PHP is even harder (they frequently make incompatible changes).

I am assuming that you believe these two environments have identical data. Construct a test case which demonstrates, with known data, what output you're expecting and what output you're getting. Post that then people might be able to tell what you're trying to do.