Selectize.define("combodo_min_items", function (aOptions) { // Selectize instance let oSelf = this; // Plugin options aOptions = $.extend({ minItems: 0, errorTitle: 'This change is not allowed', errorMessage: 'Minimum ' + aOptions.minItems + ' item(s) required.' }, aOptions ); // Override removeItem function oSelf.removeItem = (function () { let oOriginal = oSelf.removeItem; return function () { if(oSelf.items.length <= aOptions.minItems) { CombodoModal.OpenErrorModal(aOptions.errorMessage, { title: aOptions.errorTitle }); return; } return oOriginal.apply(this, arguments); } })(); });