如何在Kendo Angular Date Picker上限制文字输入？

import { Component, ViewChild } from '@angular/core';
import { DatePickerComponent } from '@progress/kendo-angular-dateinputs';

@Component({
  selector: 'app-datepicker',
  template: `
    <kendo-datepicker #datepicker></kendo-datepicker>
  `
})
export class DatepickerComponent {
  @ViewChild('datepicker', { static: true }) datepicker: DatePickerComponent;

  ngAfterViewInit() {
    const inputElement = this.datepicker.input.nativeElement;

    inputElement.addEventListener('keydown', (event) => {
      const keyCode = event.keyCode || event.which;
      const key = event.key;

      // 检查用户输入的是文本字符
      if (keyCode >= 65 && keyCode <= 90 || keyCode >= 97 && keyCode <= 122) {
        event.preventDefault();
      }

      // 或者使用正则表达式验证用户输入的文本
      // const pattern = /[a-zA-Z]/;
      // if (pattern.test(key)) {
      //   event.preventDefault();
      // }
    });
  }
}