PHP function variable parameters

Question

I want to make an update function to update a profile in my DB. Now I have all 20 fields and wants to make a feature where when I can say what data I send it.

Example:

function send_data($a, $b, $c, $d, $e, $id){
    $sql = "UPDATE table SET a=$a, b=$b, c=$c, d=$d, e=$e  WHERE id = $id";
    mysql_query($sql);
}

Now I want to call this function and for example only give A and D

Can this be? if so how?

score 4 · Accepted Answer · answered Apr 15 '14 at 13:58

4

Consider using an array:

function send_data($data, $id) {
    $build = array();
    foreach($data as $k=>$v) {
        $build[] = "`".$k."` = '".mysql_real_escape_string($v)."'";
    }
    $sql = "UPDATE `table` SET ".implode(", ",$build)." WHERE `id`=".intval($id);
    mysql_query($sql);
}

answered Apr 15 '14 at 13:58

Niet the Dark Absol

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@PeterdeBeer, [the `mysql_*` functions are deprecated](http://stackoverflow.com/questions/12859942/why-shouldnt-i-use-mysql-functions-in-php). New code should use either the [`mysqli_*` functions](http://ca2.php.net/manual/en/class.mysqli.php) or [PDO](http://ca2.php.net/manual/en/book.pdo.php) instead. – ChrisGPT was on strike Apr 15 '14 at 14:26
@Chris What is best mysqli or PDO ? – Peter de Beer Apr 15 '14 at 14:28
@PeterdeBeer, definitely opinion-based, but I'd recommend PDO. – ChrisGPT was on strike Apr 15 '14 at 14:29

score 0 · Answer 2 · answered Apr 15 '14 at 13:59

It is possible in PHP to have default parameters, for example:

function send_data($a, $b = 5, $c = 6, $d = "foo")

Which then can be called by only specifying the arguments without a default value, so this function could be called with 1-4 parameters. The issue then is that you still have to provide arguments in the correct positions, so you can't just specify $a and $d. For example, all the following are valid

send_data(5);                    // Actually send_data(5, 5, 6, "foo");
send_data(5, 3);                 // Actually send_data(5, 3, 6, "foo");
send_data(5, 1, 9);              // Actually send_data(5, 3, 9, "foo");
send_data(5, 1, 9, "bar");       // Actually send_data(5, 3, 9, "bar");

PHP doesn't support keyword arguments either, so another way is to pass in an array, for example:

function send_data($args) {
    do_something_with($args['a']);
}

score 0 · Answer 3 · answered Apr 15 '14 at 14:05

function send_data( $setData )
  {
    $setVals = array();
    foreach( $setData as $field => $val )
    {
      $value      = mysql_real_escape_string($val);
      $setVals[]  = $field . "='{$value}'";
    }

    $setString = implode(', ', $setVals);

    mysql_query('UPDATE table SET ' . $setString)
  }

score 0 · Answer 4 · answered Apr 15 '14 at 14:06

you can use default parameters in your function by defining the values in the declaration, but as far as i know you cannot "skip" arguments, like when you have the queue $a, $b, $c, you cannot call the function like myfunction(valueforA,, valueforC ). you have to give in every argument from the start until the last one you want to set. like myfunction (valueforA, NULL, ValueforC);

in your case you could use the following:

function send_data($a=NULL, $b=NULL, $c=NULL, $d=NULL, $e=NULL, $id=NULL){
    $sql = "UPDATE table SET a=$a, b=$b, c=$c, d=$d, e=$e  WHERE id = $id";
    mysql_query($sql);

and use it like

send_data(1, 2, NULL, NULL, NULL, 5);

See http://www.php.net/manual/en/functions.arguments.php

PHP function variable parameters

4 Answers4