import { FormControl } from '@angular/forms';
export declare class NaForm {
    constructor();
    /**
     * 可为空
     *
     * @param {*} [defaultValue]
     * @returns {FormControl}
     * @memberof NaForm
     */
    empty(defaultValue?: any): FormControl;
    /**
     * 必输字段
     *
     * @param {*} [defaultValue=null]
     * @returns {FormControl}
     * @memberof NaForm
     */
    required(defaultValue?: any): FormControl;
    /**
     * 密码
     *
     * @param {*} [defaultValue='']
     * @returns {FormControl}
     * @memberof NaForm
     */
    password(defaultValue?: any): FormControl;
}