如何在不使用foreach的情况下获得字典中嵌套列表的数量总和？

I want to get the total number of items in the Lists in the following Dictionary:

我想在以下词典中获取列表中的项目总数:

Dictionary<int, List<string>> dd = new Dictionary<int, List<string>>() {
    {1, new List<string> {"cem"}},
    {2, new List<string> {"cem", "canan"}},
    {3, new List<string> {"canan", "cenk", "cem"}}
};

// This only returns an enumerated array.
var i = (from c in dd
         select c.Value.Count).Select(p=>p);

5 个解决方案

#1

I believe this will get you the count you want efficiently and clearly. Under the hood it has to iterate through the lists, but to get a total count, there is no way to avoid this.

我相信这会让你有效而清晰地获得你想要的数量。在引擎盖下,它必须遍历列表,但为了获得总计数,没有办法避免这种情况。

var i = dd.Values.Sum(x => x.Count);

#2

var i = dd.Values.SelectMany(v => v).Count();

#3

Total count of all list items:

所有列表项的总数:

dd.SelectMany(i => i.Value).Count();

List containing individual list counts:

包含单个列表计数的列表:

dd.Select(i => i.Value.Count).ToList()

#4

How about this?

这个怎么样?

var l = dd.Select(i => new {i, i.Value.Count});

#5

var total = dictionary.Sum(x => x.Value.Count());

#1