WPF DataGrid 取消选择更改

Question

我正在以 MVVM 方式使用 WPF DataGrid，但无法从 ViewModel 恢复选择更改。

有没有经过验证的方法可以做到这一点？我最新试用的代码如下。现在，我什至不介意在隐藏代码内部进行黑客攻击。

public SearchResult SelectedSearchResult
{
    get { return _selectedSearchResult; }
    set
    {
        if (value != _selectedSearchResult)
        {
            var originalValue = _selectedSearchResult != null ? _selectedSearchResult.Copy() : null;
            _selectedSearchResult = value;
            if (!DispatchSelectionChange(value)) // Returns false if the selection has to be cancelled.
            {
                _selectedSearchResult = originalValue;
                // Invokes the property change asynchronously to revert the selection.
                Dispatcher.CurrentDispatcher.BeginInvoke(DispatcherPriority.ContextIdle, new Action(() => NotifyOfPropertyChange(() => SelectedSearchResult)));
                return;
            }
            NotifyOfPropertyChange(() => SelectedSearchResult);
        }
    }
}

Answer 1

经过几天的反复试验，终于成功了。以下是代码:

    public ActorSearchResultDto SelectedSearchResult
    {
        get { return _selectedSearchResult; }
        set
        {
            if (value != _selectedSearchResult)
            {
                var originalSelectionId = _selectedSearchResult != null ? _selectedSearchResult.Id : 0;
                _selectedSearchResult = value;
                if (!DispatchSelectionChange(value)) // Returns false if the selection has to be cancelled.
                {
                    // Invokes the property change asynchronously to revert the selection.
                    Dispatcher.CurrentDispatcher.BeginInvoke(DispatcherPriority.ContextIdle, new Action(() => RevertSelection(originalSelectionId)));
                    return;
                }
                NotifyOfPropertyChange(() => SelectedSearchResult);
            }
        }
    }

    private void RevertSelection(int originalSelectionId)
    {
        _selectedSearchResult = SearchResults.FirstOrDefault(s => s.Id == originalSelectionId);
        NotifyOfPropertyChange(() => SelectedSearchResult);
    }

此处的关键是使用来自数据绑定(bind)网格集合(即:SearchResults)的全新最初选择的项目，而不是使用所选项目的副本。看起来很明显，但我花了几天时间才弄明白!感谢所有帮助过的人:)