vBulletin Manual - Function Naming

Custom function names should (as far as possible) describe what they are going to do, so that a person reading the code would have a good idea of how to use and what to expect from a function simply by looking at the name.

Custom function names should be all lower-case and should use underscores to separate words.

$var2 = issomething($var1);

$var2 = isSomething($var2);

$var2 = is_something($var1);

Custom function names should adhere to the following standards

Group Prefix	Group Explanation	Example Functions
print_	Functions that directly print out code to the browser or output buffer via echo or print statements.	print_input_row print_standard_error print_cp_header
construct_	Functions that return variables containing HTML for later printing.	construct_edit_toolbar construct_forum_jump
is_ contains_	Functions that return true/false based on conditions.	is_valid_email is_wysiwyg_compatible contains_bbcode_img_tags
can_	Functions that return true/false based on permissions.	can_moderate can_administer can_announce
verify_	Functions that check conditions and directly drop out to an error message if certain conditions are met.	verify_ip_ban verify_post_errors verify_word_allowed
convert_	Functions that convert the input variable from one data format to another.	convert_kb_to_mb convert_html_to_bbcode convert_bits_to_array
cache_	Functions that read data from the database (usually) and create PHP cache variables to lighten the SQL load.	cache_templates cache_forums cache_birthdays
fetch_	Functions that return arrays / strings / integers etc. If the data type to be returned is not explicit in the function name (such as fetch_template, fetch_userinfo etc.) then specify the type of data in the function name, such as fetch_template_update_sql, fetch_replaced_session_url, fetch_reminders_array etc.	fetch_template fetch_user_search_sql fetch_user_location_array
process_	Functions that perform actions upon an array in order to prepare it for later reference.	process_thread_array process_post_preview process_online_location
build_	Functions that save data back to the database for later retrieval, such as caching birthdays into the datastore, rebuilding the style table etc.	build_bbcode_cache build_new_post build_attachment
delete_	Functions that delete something from the database.	delete_thread delete_post_index delete_user_pms
undelete_	Functions that reverse a soft deletion.	undelete_thread undelete_post
import_	Functions from the bbimport system that take an array of data and insert it as a post/thread/user (etc.) record into the database.	import_thread import_post import_user
sanitize_	Functions that make perform actions on the input parameters in order to make them safe for the next step, such as removing illegal characters, checking that a date is valid, that a $perpage value makes sense etc.	sanitize_perpage sanitize_url sanitize_reminder_date
parse_	Functions that initialize the bbcode parsing process in some way.	parse_bbcode parse_usernote_bbcode parse_pm_bbcode
handle_	Functions that are called by the bbcode parser to deal with a particular bbcode type.	handle_bbcode_img handle_bbcode_list handle_bbcode_parameter
file_	Functions that deal directly with the filesystem.	file_read file_download file_append
log_	Functions that append to one of vBulletin's logs.	log_admin_action log_vbulletin_error log_upgrade_step
exec_	Functions that actually perform an action rather than returning something.	exec_shutdown exec_queries exec_cron
sort_	Functions that sort data.	sort_search_items sort_threaded_posts
strip_	Functions that strip elements from strings	strip_bbcode strip_blank_ascii strip_empty_bbcode
xml_	Functions that work to read or output XML.	xml_import_style xml_parse_language_otag xml_escape_cdata
vb_ vb	Functions that replace built-in PHP functions with vBulletin replacements designed to extend functionality or otherwise alter the behavior of the built-in function. If the original function name contains underscores, prefix with 'vb_' otherwise prefix with 'vb'.	vbmail vb_number_format vbsetcookie
js_	Javascript functions defined within the PHP code (rather than being in one of the .js files).	js_dots js_confirm_clear_db js_forum_jump