对于Button Click我正在通过以下代码进行订阅和取消订阅Cell事件

cell.btn_Click.Tag = indexPath.Row;
cell.btn_Click.TouchUpInside -= BtnClickEvent;
cell.btn_Click.TouchUpInside += BtnClickEvent;

当我再次调用数据api并设置为TableView时,这不能正常工作.

说明：
当我打开ViewController第一次单元格按钮时单击事件触发1次.然后我第二次打开它会点击2次单击按钮事件.我使用高级代码进行订阅和取消订阅按钮事件,然后为什么它会多次调用.

我在iOS 11.2中遇到的这个问题

第一种方式：

源类完整代码

class StockListSourceClass : UITableViewSource
{
    private List<PacketAndPacketDetailItem> stockLists;
    private List<string> serialNoList;
    private UINavigationController navigationController;
    public static event EventHandler BtnClickEvented;


    public StockListSourceClass(List<PacketAndPacketDetailItem> stockLists,List<string> serialNolist,UINavigationController navigationController)
    {
        this.stockLists = stockLists;
        this.serialNoList = serialNolist;
        this.navigationController = navigationController;
    }

    public override UITableViewCell GetCell(UITableView tableView,NSIndexPath indexPath)
    {
        StockTableViewCell cell = tableView.DequeueReusableCell(StockTableViewCell.Key) as StockTableViewCell ?? StockTableViewCell.Create();
        var item = stockLists[indexPath.Row];
        if (serialNoList.Contains(item.SerialNo))
            cell.BindData(item,true);
        else
            cell.BindData(item,false);

        cell.SelectionStyle = UITableViewCellSelectionStyle.None;
        cell.PreservesSuperviewLayoutMargins = false;
        cell.SeparatorInset = UIEdgeInsets.Zero;
        cell.LayoutMargins = UIEdgeInsets.Zero;
        cell.SetNeedsLayout();
        cell.LayoutIfNeeded();

        cell.btn_Click.Tag = indexPath.Row;


        cell.btn_Click.TouchUpInside -= BtnClickEvent;
        cell.btn_Click.TouchUpInside += BtnClickEvent;

        cell.btn_Click.TouchUpInside += (sender,e) => {
            var imageName = ((UIButton)sender).TitleLabel.Text;
            if (imageName.Equals("unchecked"))
            {
                ((UIButton)sender).SetBackgroundImage(UIImage.FromBundle("checked"),UIControlState.Normal);
                ((UIButton)sender).TitleLabel.Text = "checked";
            }
            else
            {
                ((UIButton)sender).SetBackgroundImage(UIImage.FromBundle("unchecked"),UIControlState.Normal);
                ((UIButton)sender).TitleLabel.Text = "unchecked";
            }
        };

        return cell;
    }

    public void BtnClickEvent(object sender,EventArgs e)
    {
        var row = ((UIButton)sender).Tag;
        MarketSheetViewController.RowNo = (int)row;
        if (BtnClickEvented != null)
        {
            BtnClickEvented(stockLists[(int)row].SerialNo,EventArgs.Empty);
        }
    }

    public override nint RowsInSection(UITableView tableview,nint section)
    {
        return stockLists.Count;
    }

    public override void RowSelected(UITableView tableView,NSIndexPath indexPath)
    {
        var storyboard = UIStoryboard.FromName("Main",null);
        var webController = storyboard.InstantiateViewController("PacketDetailViewController") as PacketDetailViewController;
        webController.item = stockLists[indexPath.Row];
        this.navigationController.PushViewController(webController,true);
    }
}

在ViewController里面我用它

StockListSourceClass.BtnClickEvented += (sender,e) =>
{
    if (!(serialNoList.Contains(stockLists[RowNo].SerialNo)))
        serialNoList.Add(stockLists[RowNo].SerialNo);
    else
        serialNoList.Remove(stockLists[RowNo].SerialNo);
    SetUpperPanelData();
};

第二种方式

cell.btn_Click.TouchUpInside += (sender,e) => {

    var imageName = ((UIButton)sender).TitleLabel.Text;
    if (imageName.Equals("unchecked"))
    {
        ((UIButton)sender).SetBackgroundImage(UIImage.FromBundle("checked"),UIControlState.Normal);
        ((UIButton)sender).TitleLabel.Text = "checked";
    }
    else
    {
        ((UIButton)sender).SetBackgroundImage(UIImage.FromBundle("unchecked"),UIControlState.Normal);
        ((UIButton)sender).TitleLabel.Text = "unchecked";
    }
    var row = ((UIButton)sender).Tag;
    MarketSheetViewController.RowNo = (int)row;
    if (BtnClickEvented != null)
    {
        BtnClickEvented(stockLists[(int)row].SerialNo,EventArgs.Empty);
    }
};

但是如果我第二次打开ViewController,则会多次调用此方法.