export declare const isElement: (e: unknown) => e is Element;
export declare const trim: (string: string) => string;
export declare function hasClass(el: HTMLElement, cls: string): boolean;
/**
 *
 * @param {*} el 元素
 * @param {*} cls 类名
 */
export declare function addClass(el: HTMLElement, cls: string): void;
/**
 *
 * @param {*} el 元素
 * @param {*} cls 类名
 */
export declare function removeClass(el: HTMLElement, cls: string): void;
/**通过 tagName 获取指定元素下的元素 */
export declare const getElementsByTagName: (el: HTMLElement, tagName: string) => Element[];