Why am I getting the 'Trying to get property of non-object' error when accessing database results?

Trying to Access Property of Non-Object

While attempting to retrieve data from a database, you encounter the error "Trying to get property of non-object." This error occurs when you try to access a property of a null or non-existent object.

In your specific scenario, you have the following code on your Control page:

$results = mysql_query("SELECT * FROM sidemenu WHERE `menu_id`='".$menu."' ORDER BY `id` ASC LIMIT 1", $con);
$sidemenus = mysql_fetch_object($results);

And on your View page:

foreach ($sidemenus as $sidemenu): 
  echo $sidemenu->mname."<br />";
endforeach; 

The error originates because mysql_fetch_object() returns an object, not an array of objects. Therefore, in the View page, you attempt to iterate over a non-iterable object, which leads to the error.

Solution:

To resolve the issue, you should either:

• Convert the result to an array:

$results = mysql_query("SELECT * FROM sidemenu WHERE `menu_id`='".$menu."' ORDER BY `id` ASC LIMIT 1", $con);

$sidemenus = array();
while ($sidemenu = mysql_fetch_object($results)) {
    $sidemenus[] = $sidemenu;
}

This will convert the results into an array of objects, which you can then iterate over in your View page.

• Use PDO:

PDO provides a more modern and efficient way to interact with databases. PDOStatement::fetchAll(PDO::FETCH_OBJ) returns an array of objects, similar to the functionality you were expecting from mysql_fetch_object().

$stmt = $con->prepare("SELECT * FROM sidemenu WHERE `menu_id` = :menu_id ORDER BY `id` ASC LIMIT 1");
$stmt->bindParam(':menu_id', $menu);
$stmt->execute();

$sidemenus = $stmt->fetchAll(PDO::FETCH_OBJ);

By utilizing either of these solutions, you can retrieve the data from the database and avoid the error "Trying to get property of non-object."

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