MySQLI binding params using call_user_func_array

Question

Please see below my code. I am attempting to bind an array of paramenters to my prepared statement. I've been looking around on the web and can see I have to use call_user_func_array but cannot get it to work. The error I get is: "First argument is expected to be a valid callback, 'Array' was given" I may be wrong but I'm assuming the first argument can be an an array and perhaps this error message is misleading. I think the issue is that my array is in someway at fault. Can anyone see what I am doing wrong? Thanks.

$type = array("s", "s");
$param = array("string1","anotherstring");

$stmt = $SQLConnection->prepare("INSERT INTO mytable (comp, addl) VALUES (?,?)");

$params = array_merge($type, $param);

call_user_func_array(array(&$stmt, 'bind_param'), $params);
$SQLConnection->execute();

Answer 1

It must be like this:

//connect
$mysqli = new mysqli($host, $user, $password, $db_name);

//prepare
$stmt = $mysqli->prepare("SELECT * FROM the_table WHERE field1= ? AND Field2= ?");

//Binding parameters. Types: s = string, i = integer, d = double,  b = blob
$params= array("ss","string_1","string_2");

//now we need to add references
$tmp = array();
foreach($params as $key => $value) $tmp[$key] = &$params[$key];
// now us the new array
call_user_func_array(array($stmt, 'bind_param'), $tmp);

$stmt->execute();

/* Fetch result to array */
$res = $stmt->get_result();
while($row = $res->fetch_array(MYSQLI_ASSOC)) {
  $a_data[]=$row;
}
print_r($a_data);

$stmt->close();

Answer 2

Since PHP 5.6, you don't have to mess around with call_user_func_array() anymore.

Instead of:

$stmt->bind_param($param_types, $my_params_array);

you can just use the splat operator, like this:

$stmt->bind_param($param_types, ...$my_params_array); // exact code