PHP get single value from MySQL with variable [duplicate] - php

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Call to a member function prepare() on a non-object PHP Help [duplicate]
(8 answers)
Closed 2 years ago.
I can't seem to get simple query working to find UserID from the table of Users by UserEmail
I have simple function to suppose to return UserID
functions.php
function get_userID($UEml)
{
// Check database connection
if( ($DB instanceof MySQLi) == false) {
return array(status => false, message => 'MySQL connection is invalid');
}
$qSQL = "SELECT UsID FROM Users WHERE UsEml=? LIMIT 1";
$qSQL = $DB->prepare($qSQL);
$UEml = $DB->real_escape_string($UEml);
$qSQL->bind_param("s", $UEml);
$qSQL->execute();
$result = $qSQL->get_result();
while ($row = $result->fetch_row()) {
return $row[0];
}
// return $row[0];
if($qSQL) {
return array(status => true);
}
else {
return array(status => false, message => 'Not Found');
}
}
and I call it from php script
check-User.php
<?php
require_once("db-config.php");
include 'functions.php';
...
$UsID = get_userID("joe#example.com");
echo 'UserID: <span style="color: blue">'. $UsID ."</span>";
...
?>
db-config.php
<?php
// Two options for connecting to the database:
define('HOST_DIRECT', 'example.com'); // Standard connection
define('HOST_LOCAL', '127.0.0.1'); // Secure connection, slower performance
define('DB_HOST', HOST_DIRECT); // Choose HOST_DIRECT or HOST_STUNNEL, depending on your application's requirements
define('DB_USER', 'dbUser'); // MySQL account username
define('DB_PASS', 'SecretPas'); // MySQL account password
define('DB_NAME', 'DBName'); // Name of database
// Connect to the database
$DB = new MySQLi(DB_HOST, DB_USER, DB_PASS, DB_NAME);
if ($DB->connect_error) {
die("Connection failed: " . $DB->connect_error);
}
//echo "Connected successfully";
?>
I tried many variations, but no luck and also checked many similar posts here, but just can't get it working.
Thanks

Answer 1

You have a couple of errors here:
$DB is not available in the function
the echo statement is wrong
This is the code without these 2 errors:
function get_userID($DB, $UEml)
{
// Check database connection
if ( ($DB instanceof MySQLi) == false) {
return array(status => false, message => 'MySQL connection is invalid');
}
$qSQL = "SELECT UsID FROM Users WHERE UsEml=? LIMIT 1";
$qSQL = $DB->prepare($qSQL);
$qSQL->bind_param("s", $UEml);
$qSQL->execute();
$result = $qSQL->get_result();
while ($row = $result->fetch_row()) {
return $row[0];
}
// return $row[0];
// I do not know why you wrote this code. If you get an user this code will not be executed
if ($qSQL) {
return array(status => true);
} else {
return array(status => false, message => 'Not Found');
}
}
And your echo:
// ...
$UsID = get_userID($DB, "joe#example.com");
echo "UserID: <span style=\"color: blue\">{$UsID}</span>";