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fires before a control or its checkbox is hidden

beforeHide: (value: {[id: string]: boolean | string}, id?: string, init?: boolean) => boolean | void;


  • value: object - the current value of the control. The object contains a set of key:value pairs where the key is the id of a checkbox and the value is the value/state of the checkbox.
  • id?: string - optional, the ID of a checkbox of the control
  • init?: boolean - optional, true, if the event is triggered on the control initialization; otherwise, false


Return false to prevent a control or its checkbox from being hidden; otherwise, true.


form.getItem("CheckboxGroup").events.on("beforeHide", function(value, id, init) {
console.log("beforeHide", value, id, init);
return true;

Related sample: Form. Hide/Show control

Change log:

The id parameter was added in v8.0