请帮我解决Linq的问题

Question

我正在尝试获取Class属性等于selectedIClassesList中的一个值的所有资产;

这样的事情：

from x in Assets where selectedIClassesList.Contains(x.Class) select x

Answer 1

你可以加入......

var query = from a in Assets
            join s in selectedClassesList on a.Class equals s
            select a;

Answer 2

Assets.Where(x=>selectedIClassesList.Contains(x.Class));

Answer 3

如果我理解正确，你的问题是IClassesList没有contains方法吗？如果IClassesList是与x.Class相同类型的对象的IEnumerable，那么这应该可行。

from x in Assets where selectedIClassesList.Any(s => s == x.Class) select x

为了获得更好的性能，你最好创建一个字典。

var selectedClassesDict = selectedIClassesList.ToDictionary(s => s);
var selectedAssets = from a in Assets 
                     where selectedClassesDict.ContainsKey(a.Class)
                     select a;