角度输入模式验证，无法读取未定义的属性“ match”

Question

嗨，我有一个带有模式的输入字段，我正在编写一个if条件来验证该模式，但是当我单击保存时，它显示.match模式未定义如何解决此错误，我想同时验证输入为空和模式不匹配时

                      <input
                      #bankName="ngModel"
                      type="text"
                      class="form-control ng-pristine ng-invalid ng-invalid-required"
                      [(ngModel)]="item.local_institution_name"
                      name="LocalinstitutionNameChina"
                      [pattern]="chinaValidator"
                      [ngClass]="{
                       invalid:
                       (submitted && (bankName.errors?.pattern || bankName.errors?.required)) ||
                       (bankName.errors?.pattern && item.institution_name == true)
                      }"
                    />
 if (
      payload.item.chinaCase &&
      payload.item.routingLabel == 'CNAPS Code' &&
      payload.item.local_institution_name ==='' || 
      payload.item.local_institution_name === null ||
      payload.item.local_institution_name ===undefined &&
      !payload.item.local_institution_name.match(this.chinaValidator)

    ) {
      this.loader = false;
      this.toaster.pop('error', `Bank Name`, `Invalid:  should be Simplified Chinese characters - 简化字`);
      return;

    }