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fires before a Form control is shown

beforeShow: (name: string, value?: any) => boolean | void;


  • name|id: string - the name (or id, if the name is not specified) of the Form control
  • value: any - the current value of the control


Return false to prevent a control from being shown; otherwise, true.

Example"beforeShow", function(name, value) {    console.log("beforeShow", name, value);     return false;});

Related sample: Form. Events

Change log:

  • added in v6.5
  • Before v7.0, the event took one parameter - the control id.
  • Starting from v7.0, the event takes two parameters: name|id and value.