C#对字典使用Linq查询

Dictionary<int, int> dic = new Dictionary<int, int>();dic.Add(1, 2);dic.Add(2, 3);dic.Add(3, 4);dic.Add(4, 5);dic.Add(5, 6);//筛选键var keys = dic.Where(item => item.Key > 2).Select(item => item.Key);foreach (var item in keys){Console.WriteLine($"key:{item }");}//筛选值var values = dic.Where(item => item.Value>3).Select(item =>item.Value  );foreach (var item in values){Console.WriteLine($"value:{item }");}//筛选键值对var keyValue = dic.Where(item => item.Key > 2).ToList();foreach (var item in keyValue){Console.WriteLine($"key:{item.Key },value:{item.Value }");}//创建一个新的字典Dictionary<int, int> dicNew = dic.Where(item => item.Key > 2).ToDictionary(item => item.Key, item => item.Value);foreach (var item in dicNew){Console.WriteLine($"key:{item.Key },value:{item.Value }");}