How can I filter List property

问题

On my View I have a AutoSuggestBox(searchfield) and ListView, my ListView's ItemSource is bounded to my VM Class property:

private Class1 _searchMatches;
public Class1 SearchMatches {
    get { return _searchMatches; }
    set { this.Set(ref _searchMatches, value); }
}

On My Class1 I have a LoadItems Task:

async Task> LoadItems()

var stocks = _response.products?
                .Select(s => new MyClass(PLService.DtoToModel(s)))
                .ToList();
        var items = stocks.GroupBy(p => p.productModel.Description)
                                .Select(p => p.First())
                                .ToList();
        return items;

When i type test on the AutoSuggestBox and hit enter, What is the simplest way to filter items where(item.description == searchterm)? just filter it and update itemsource, not rewriting the property

回答1:

You can use <SearchBox> and it's QuerySubmitted event. But it will work well with <TextBox> too. If you need to refilter your Items - just create two lists, one to store your Items and another for items displaying.

Here is a <SearchBox> sample:

private List<MyClass> _items; // store for your items

private List<MyClass> _displayItems;
public List<MyClass> DisplayItems // list to show
{
    get { return _displayItems; }
    set { SetProperty(ref _displayItems, value); }
}

private void SearchBoxQuerySubmitted(SearchBoxQuerySubmittedEventArgs eventArgs)
{
   searchTerm = eventArgs.QueryText?.Trim();
   Filter(searchTerm);
}

private void Filter(string searchTerm)
{
   if (_items == null)
       return;

   IQueryable<MyClass> items = _items.AsQueryable();

   if (!string.IsNullOrEmpty(searchTerm))
   {
      searchTerm = searchTerm.ToLower();
      items = items.Where(x => x.productModel.Description.ToLower().Contains(searchTerm));
   }

   DisplayItems = items.ToList();
}

来源：https://stackoverflow.com/questions/45363486/how-can-i-filter-list-property

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