Why Does `mysqli_stmt::bind_param()` Require References, and How Can I Fix the 'Parameter Expected to be a Reference' Error?

Troubleshooting "mysqli bind_param() Parameter Expected to be a Reference" Errors

The error "Parameter 3 to mysqli_stmt::bind_param() expected to be a reference, value given" indicates a discrepancy between the expected type of input and the provided value in the mysqli_bind_param() method.

In the given code, you're using call_user_func_array() to pass an array of values to mysqli_stmt_bind_param(). However, mysqli_bind_param() expects the parameters to be passed by reference, while call_user_func_array() accepts either references or values.

To rectify this issue, you can use the following solution provided in the PHP documentation:

$refs = array();
foreach ($params as $key => $value)
    $refs[$key] = &$params[$key];
call_user_func_array(array($statement, 'bind_param'), $refs);

This code creates an array of references ($refs) to the elements in the $params array and passes the $refs array to mysqli_stmt_bind_param(), ensuring that the parameters are passed by reference.

Alternatively, you can use the spread operator (available in newer PHP versions) to directly pass the elements of the $params array as references:

call_user_func_array(array($statement, 'bind_param'), ...$params);

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