C# Dictionary<key, value>

Dictionary<int, string> s;

int i = s.Single(x => x.Value =="xxx").Key;

 

Dictionary<string, string> dat = new Dictionary<string, string> ();
dat["email"] = "666666@email.com";
dat ["pas"] = "1234";
//dat.Add ("email", "ddddd@qq.com");

foreach (var r in dat) {
    Console.WriteLine (r);
}

Console.WriteLine (dat["email"]);