即使完成功能并手动清除事件后，事件处理程序也不会清除

Question

我的代码；

public RowSelectionHandler($event) {
    this.eventHandler = $event;
    if (this.eventHandler.length === 0) {
      console.log('Create');
      this.disableCreate.emit(false);
    } else if (this.eventHandler.length === 1) {
      this.disableModify.emit(false);
    } else if (this.eventHandler.length > 1) {
      this.disableDelete.emit(false);
    }
  }

 public deleteResource() {
    let cnt = 1;
    console.log(this.eventHandler);
    for (let res of this.eventHandler) {
      console.log('res ' + res.dn );
      this.facadeservice.deleteEntry(res.dn).subscribe(
        (_res) => {
          console.log('Query deleted successfully ' + cnt + ' sds');
          cnt = cnt + 1;
          this.refresh();
        },
        (err) => {
          console.log('Error occured' + err);
        });
    }
    this.deletedialog = false;
    this.eventHandler = null;
    console.log(this.eventHandler);
  }

im将$ event存储在any类型的事件处理程序中，并在deleteResource函数中使用它，但是当我在删除条目后再次调用rowselection函数时，它仍然显示未清除事件，并且我删除的元素存储在事件处理程序

我应该怎么做才能清除事件处理程序