WPF datagrid过滤器数据绑定列表，列表 c#

I have a DataGrid binding to a List<T>. Below is my class. The List<FSCLevel> is binding to the RowDetails in my main DataGrid. I have added a filter control for users to filter through CUSTOMER_CODE.

我有一个DataGrid绑定到的列表。下面是我的类。列表绑定到我的主DataGrid中的行细节。我为用户添加了一个过滤器控件，以便通过CUSTOMER_CODE进行过滤。

public class CUSTCARDLevel: INotifyPropertyChanged
{
    #region Members        
    private string _cUSTOMER_CODE;            
    private List<FSCLevel> _fSClist;        
    #endregion

    #region Properties       
    public string CUSTOMER_CODE { get { return _cUSTOMER_CODE; } set { _cUSTOMER_CODE = value; OnPropertyChanged("CUSTOMER_CODE"); } }      
    public List<FSCLevel> FSCLIST   { get { return _fSClist; } set {_fSClist = value;    OnPropertyChanged("FSCLIST"); } }
    #endregion

    // INotifyPropertyChanged interface
    public event PropertyChangedEventHandler PropertyChanged;
    protected void OnPropertyChanged(string propertyName) 
   {
        if (PropertyChanged != null)
        { PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }

}

I now need to apply some filters on the list, e.g. on DataGrid it only shows CUSTOMER_CODE is "CUST1".

我现在需要在列表上应用一些过滤器，例如在DataGrid上它只显示CUSTOMER_CODE是“CUST1”。

So here is the question, do I have to use an ObservableCollection for the filter purpose? Is there a way that I can just use the class with INotifyPropertyChanged interface? If so, what is the best way to handle the List<T1> within a List<T>? Say I cast my list into ObservableCollection<T> using:

这里有一个问题，我是否必须使用一个天文台来进行过滤?有没有一种方法可以使用INotifyPropertyChanged接口的类?如果是，在列表中处理列表的最佳方式是什么?假设我使用以下方法将我的列表放到ObservableCollection 中:

ObservableCollection<CUSTCARDLevel> myObserveList = new ObservableCollection<CUSTCARDLevel>(myList);

What is going to happen to the List<FSCLevel> inside? or how do I cast List<FSCLevel> inside CUSTCARDLevel into ObservableCollection? Or I need to do something to fix my class?

列表内部会发生什么?或者我如何将列表在custcardcardlevel内转换为ObservableCollection?或者我需要做点什么来修我的课?

1 个解决方案

#1

I wanted to put this as a comment but it went off the character limit. I'll get right to it.

我想把它作为一个评论，但它超出了字符限制。我马上就去做。

Well it's all about the need of the hour.

这都是关于时间的需要。

I would strongly recommend against the frequent casting using new ObservableCollection<object>(myList) since it'll each time return a new instance that'll take up memory.

我强烈建议不要频繁使用新的ObservableCollection

Now let's assume you have a List<T> and any changes in the items of the List<T> you want to reflect on the UI then you should only use an ObservableCollection for the List<T> and not for any List that are a part of Class T.

现在，假设您有一个列表，列表项中的任何更改，您想要在UI上进行反映，那么您应该只对列表的列表使用一个ObservableCollection，而不是任何属于类T的列表。

On the contrary, if you have a UI that needs to be updated each time the collection in the class T is modified, I would recommend that you make it an ObservableCollection.

相反，如果您有一个UI，每次修改类T中的集合时都需要更新它，那么我建议您将它设置为一个ObservableCollection。

Generally in the most common ways, Developers use ExtensionMethods to convert a List<T> to an ObservableCollection<T> Read more about it here

通常，在最常见的方法中，开发人员使用extensionmethod将列表转换为一个ObservableCollection 阅读更多信息

Also, they use XAML Converters and bind the element directly to the list.

此外，他们使用XAML转换器并将元素直接绑定到列表中。

My final recommendation: Use an observable collection based on your needs as explained above but most importantly, don't operate on Lists unless it's actually necessary. Fetch the data from your service into a List convert it once into an ObservableCollection and then use System.LINQ to filter the data from it.

我最后的建议是:根据您的需要使用可观察的集合，如上面所述，但最重要的是，除非确实需要，否则不要对列表进行操作。从您的服务中获取数据到列表中，将其转换为一个ObservableCollection，然后使用System。LINQ来过滤数据。

#1