{"name":"addUserActionEventHandler","operator":null,"title":"addUserActionEventHandler","type":"command","url":"https://community.bistudio.com/wiki/addUserActionEventHandler","revid":378187,"updated":"2026-03-10T13:05:46Z","groups":["Event Handlers"],"status":"ok","replaced_by":[],"games":[{"game":"arma3","name":"Arma 3","version":"2.06"}],"since":{"game":"arma3","name":"Arma 3","version":"2.06"},"arma3_since":"2.06","branch":null,"locality":{"argument":null,"effect":"local","server_exec":false},"exec":null,"description":"Adds a user action event handler to the current mission and returns its event handler index.","syntaxes":[{"syntax":"addUserActionEventHandler [keyName, event, expression]","since":null,"effect":null,"exec":null,"params":[{"name":"keyName","type":"String","optional":false,"default":null,"description":"action key name - see inputAction/actions","types":["String"],"since":null,"text":"keyName: String - action key name - see inputAction/actions"},{"name":"event","type":"String","optional":false,"default":null,"description":"event name - see UserAction Event Handlers. Can be one of:\n- `\"Activate\"`\n- `\"Deactivate\"`\n- `\"Analog\"`","types":["String"],"since":null,"text":"event: String - event name - see UserAction Event Handlers. Can be one of:\n- `\"Activate\"`\n- `\"Deactivate\"`\n- `\"Analog\"`"},{"name":"expression","type":"Code","optional":false,"default":null,"description":"expression that will be executed in missionNamespace when event handler fires.\n- `_thisEventHandler` returns the event handler index\n- `_thisEvent` returns the event type (the *event* parameter, either `\"Activate\"`, `\"Deactivate\"` or `\"Analog\"`)","types":["Code"],"since":null,"text":"expression: Code - expression that will be executed in missionNamespace when event handler fires.\n- `_thisEventHandler` returns the event handler index\n- `_thisEvent` returns the event type (the *event* parameter, either `\"Activate\"`, `\"Deactivate\"` or `\"Analog\"`)"}],"returns":{"type":"Number","types":["Number"],"description":"the index of the currently added UserAction event handler is returned","text":"Number - the index of the currently added UserAction event handler is returned"},"form":"unary","operator":null,"left":null,"right":{"text":"[keyName, event, expression]","types":["Array"]}}],"examples":[{"text":"```sqf\nprivate _ehId = addUserActionEventHandler [\"ReloadMagazine\", \"Activate\", { systemChat \"reloading!\"; }];\n```","code":["private _ehId = addUserActionEventHandler [\"ReloadMagazine\", \"Activate\", { systemChat \"reloading!\"; }];"]}],"multiplayer":null,"problems":null,"aliases":[],"see_also":["removeUserActionEventHandler","removeAllUserActionEventHandlers","Arma 3: Event Handlers"],"notes":[],"categories":["Arma 3: New Scripting Commands","Arma 3: Scripting Commands","Command Group: Event Handlers","Introduced with Arma 3 version 2.06","Scripting Commands","Scripting Commands: Local Effect"]}