c# - 检查名称是否已经在 ListView 列中

Question

我有一个包含 5 列（、、、、、）ActivityID的NameListView 。我使用此方法添加项目：DateNstudentNGuide

            // fill the activities listview within the panel with a list of activities
            List<Activity> activitiesList = activity_Service.GetActivities();

            // clear the listview before filling it again
            listViewActivities.Items.Clear();


            foreach (Activity a in activitiesList)
            {
                ListViewItem List = new ListViewItem(a.ActivityID.ToString());
                List.Tag = a;
                List.SubItems.Add(a.Name);
                List.SubItems.Add(a.Date);
                List.SubItems.Add(a.NStudent.ToString());
                List.SubItems.Add(a.NGuide.ToString());


                listViewActivities.Items.Add(List);
                //List view task (right arrow) then View and then details to see the columns
            }
        }

    }
    private void btnAddActivity_Click(object sender, EventArgs e)
    {
        int ActivityID = int.Parse(txtbActivityID.Text);
        string Name = txtbActivityName.Text;
        string Date = CBDay.GetItemText(CBDay.SelectedItem);
        activity_Service.Add_Activity(ActivityID, Name, Date);
        listViewActivities.Items.Clear();
        showPanel("Activities");
    }

我想在添加活动之前检查活动名称是否已在使用中。

你能帮我吗？