如何对数字字符串列表进行排序？ 最好使用LINQ

Question

I have a string in below manner:-

string[] things = new string[] { "1", "10", "2", "1_1", "2_1","3_1" };

The desired output is:

"1",
"1_1",
"2",
"2_1",
"3_1",
"10",

How I can achieve this using LINQ?

Answer 1

Yes there is, you can split each part by _ and convert the first string part to an integer. When sorting afterwards this will ensure that 10 is not before 2 . Then in the second step you order it according to the last number

string[] things = new string[] { "5_3", "5_2", "1", "10", "2", "1_1", "2_1", "1_2", "3_1" };

string[] ordered = things.OrderBy(x=>Convert.ToInt32(x.Split('_').First())).                       
                           ThenBy(x=>Convert.ToInt32(x.Split('_').Last())).ToArray();

Output:

EDIT: Here is the link to the documentation of ThenBy for the sake of informativity ;)

Answer 2

What about this?

string[] strings = new string[] { "1", "10", "2", "1_1", "2_1", "3_1" };

var ordered = from str in strings
                let weight = double.Parse(str.Replace("_", CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator))
                let pair = new { Weight = weight, OriginalString = str }
                orderby pair.Weight
                select pair.OriginalString;

Answer 3

This will give you the desired output:

string[] things = new string[] { "1", "10", "2", "1_1", "2_1", "3_1" };
var list =  from row in things select Decimal.Parse(row.Replace("_",CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator));
list = list.OrderBy(d=> d).ToList();
var StringList = from row in list select row.ToString("0.#").Replace(CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator, "_");

Answer 4

You can use one of the overloads of OrderBy that allows you to create your own key and maybe specify your own comparer. It looks like you want to treat _ as a decimal separator.

One quick & dirty way would be to replace _ with the decimal separator, eg :

var decSeparator=CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator;

var orderedThings=things.OrderBy(thing=>double.Parse( thing.Replace("_",decSeparator)) )
                        .ToArray();

This is quick & dirty because it assumes _ appears only once. If _ appeared multiple times, the replaced string wouldn't be a valid number

Answer 5

If that format is strict you could parse to Version and order by that:

string[] orderedThings = things
   .Select(t => new { Thing = t, Numbers = (t + "_0").Split('_') })
   .Where(x => x.Numbers.All(s => s.All(char.IsDigit)))
   .Select(x => new { x.Thing, VersionStr = String.Join(".",x.Numbers.Take(4)) })
   .OrderBy(x => new Version(x.VersionStr))
   .ThenBy(x => x.Thing)
   .Select(x => x.Thing)
   .ToArray();

The t + "_0" trick was necessary to ensure that also single digits can be parsed. A version needs at least a major and aminor part. This "works" also if there are more than 4 tokens(major, minor, build, and revision). Then only the first 4 are taken to initialize the Version instance.