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fires before changing the value of a control

beforeChange: (value: {[id: string]: boolean | string}) => boolean | void;


  • value: object - the value to be set for the control. The object contains a set of the key:value pairs where the key is the id of a checkbox and the value is the value/state of the checkbox


Return false to prevent changing the value of the control; otherwise, true.


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

Change log: The event was added in v8.0