按字符串C＃的第n个字符对列表进行排序

Question

Is there a simple way to sort a list based on the 4th character of a string? I have a list of countries with codes in front of them; "us united states" is one string in my list and I want to ignore the codes ("us ") before the full country name.

Answer 1

list.Sort((x, y) => x.Substring(3).CompareTo(y.Substring(3)));

Answer 2

Unlike the other answers, this way of performing the sort will not create unnecessary substrings. Instead, it takes advantage of the existing string.Compare(strA, indexA, strB, indexB, length) overload that accepts string offsets for comparison.

list.Sort((s1, s2) => string.Compare(s1, 3, s2, 3, int.MaxValue));

There are other useful string.Compare overloads, that also accept offset values, that you can use to tweak the comparison behavior. (eg: ignoring case, etc.)

Answer 3

This should do it - List<string> is your original list variable

[List<string>].OrderBy(s => s.Substring(3)).ToList();

This works

var l = new List<string>(){"us unites states","uk united kingdom","ca canada"};
foreach (var s in l.OrderBy(s => s.ToLower().Substring(3)).ToList())
    Console.WriteLine(s);

Note ToLower , so you don't compare upper case to lower case letters (if you have both)