目录
取值
First,FirstOrDefault
Last,LastOrDefault
Single,SingleOrDefault
ElementAt,ElementAtOrDefault
Skip,SkipWhile
Take,TakeWhile
DefaultIfEmpty
Where
检查
All
Any
Contains
OfType
SequenceEqual
Count,LongCount
计算
转换
ToList
ToArray
ToDictionary
AsEnumerable
Cast
Reverse
Distinct
Select,SelectMany
排序
OrderBy,OrderByDescending
ThenBy,ThenByDescending