What is WordPress Hook: query_vars

The query_vars hook in WordPress is used to modify the query variables before the main query is executed. It allows developers to add, remove, or modify query variables to customize the query results.

Understanding the Hook: query_vars

The query_vars hook is located within the parse_request function in the WordPress core. This function is responsible for parsing the request to determine which query variables should be set based on the request URL.

Hook Parameters (if applicable): query_vars

The query_vars hook does not accept any specific parameters, as it is used to modify the query variables directly within the function.

Hook Doesn’t Work: query_vars

If the query_vars hook doesn’t work as expected, it could be due to conflicts with other plugins or themes that are also modifying the query variables. It is recommended to deactivate other plugins or switch to a default theme to troubleshoot the issue.

Best Practices & Usage Notes (if applicable): query_vars

When using the query_vars hook, it is important to be mindful of the order in which the hook is executed, as other plugins or themes may also be modifying the query variables. It is best practice to document any modifications made to the query variables for future reference.

query_vars Usage Example: query_vars

“`php
function custom_query_vars($query_vars) {
$query_vars[] = ‘custom_var’;
return $query_vars;
}
add_filter(‘query_vars’, ‘custom_query_vars’);
“`
In this example, the custom_query_vars function adds a new query variable ‘custom_var’ to the list of query variables. This allows developers to use this custom variable in their custom queries or templates.