调试php。 文件和行

Question

I'm working on an older script. Someone told me that the script uses ancient way of debugging (file and line).

I've posted an example of the script. What should I be using instead of the FILE and LINE method?

mysql class -

 function error($file, $line) {
            trigger_error("DB error in *<b>{$file}</b>* on line <b>{$line}</b><br />
 " . mysql_error() . "" . @mysql_error($this->dbl), E_USER_ERROR);
        }


      function query($query, $file, $line) {

            $result = mysql_query($query) or $this->error($file, $line);
            $this->num_queries++;

            return $result;
        }

Standard query -

$DB->query("SELECT * FROM table"), __FILE__, __LINE__);

Answer 1

Realistically, you should be using debug_backtrace for this.

Eg:

function error(){
    $trace = debug_backtrace();
    $file = $trace[1]['file']; // use 1 because you don't want
                               // to include this function!
                               // 2 will be the function which called the function 
                               // which called this function.
    $line = $trace[1]['line'];
    trigger_error("DB error in *<b>{$file}</b>* on line <b>{$line}</b><br />
 " . 
                  // You really should consider using MySQLi instead of MySQL
                  mysql_error() . "" . @mysql_error($this->dbl), E_USER_ERROR);
                  // why do you have two mysql_error calls???
}