排序計算不同的獨特OCCURENCES使用LINQ

Question

我想知道如何在下面的列表中使用LINQ下降最OCCURENCES的順序進行排序：

ghj 
def 
abc 
def 
abc 
abc 

到：

abc 
def 
ghj 

我要找的lambda表達式。

Answer 1

string[] names = { "ghj", "def", "abc", "def", "abc", "abc" }; 

IEnumerable<string> query = names 
    .GroupBy(s=>s) // groups identical strings into an IGrouping 
    .OrderByDescending(group => group.Count()) // IGrouping is a collection, so you can count it 
    .Select(group=>group.Key); // IGrouping has a Key, which is the thing you used to group with. In this case group.Key==group.First()==group.skip(1).First() ... 

Answer 2

如果你想獲得由事件下令不同列表，使用組方：

var query = foo.GroupBy(xx => xx) 
       .OrderByDescending(gg => gg.Count()) 
       .Select(gg => gg.Key); 
// on your input returns: 
// abc 
// def 
// ghj