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c#linqsortingcompareicomparer

Sorting a list by numeric value, alphabetic value and then a symbol


Hi i have been racking my brains to figure a way to do this but i cant. Lets say I have the following list:

1
2
'
@
r
r2
r1

I would like it to be sorted to the following order

1
2
r
r1
r2
'
@

I have the following code (cant figure out where to do the sorting of symbols last)

void Main()
{


List<string> list = new List<string>();
list.Add("1");
list.Add("2");
list.Add("'");
list.Add("@");
list.Add("r");
list.Add("r2");
list.Add("r1");
list.Sort(new AlphanumComparatorFastString());

}

public class AlphanumComparatorFastString : IComparer<String>
{
    public int Compare(string s1, string s2)
    {
        if (s1 == null)
            return 0;

        if (s2 == null)
            return 0;

        int len1 = s1.Length;
        int len2 = s2.Length;
        int marker1 = 0;
        int marker2 = 0;

        // Walk through two the strings with two markers.
        while (marker1 < len1 && marker2 < len2)
        {
            char ch1 = s1[marker1];
            char ch2 = s2[marker2];

            // Some buffers we can build up characters in for each chunk.
            char[] space1 = new char[len1];
            int loc1 = 0;
            char[] space2 = new char[len2];
            int loc2 = 0;

            // Walk through all following characters that are digits or
            // characters in BOTH strings starting at the appropriate marker.
            // Collect char arrays.
            do
            {
                space1[loc1++] = ch1;
                marker1++;

                if (marker1 < len1)
                {
                    ch1 = s1[marker1];
                }
                else
                {
                    break;
                }
            } while (char.IsDigit(ch1) == char.IsDigit(space1[0]));

            do
            {
                space2[loc2++] = ch2;
                marker2++;

                if (marker2 < len2)
                {
                    ch2 = s2[marker2];
                }
                else
                {
                    break;
                }
            } while (char.IsDigit(ch2) == char.IsDigit(space2[0]));

            // If we have collected numbers, compare them numerically.
            // Otherwise, if we have strings, compare them alphabetically.
            string str1 = new string(space1);
            string str2 = new string(space2);

            int result;

            if (char.IsDigit(sp`enter code here`ace1[0]) && char.IsDigit(space2[0]))
            {
                int thisNumericChunk = int.Parse(str1);
                int thatNumericChunk = int.Parse(str2);
                result = thisNumericChunk.CompareTo(thatNumericChunk);
            }
            else
            {
                result = str1.CompareTo(str2);
            }

            if (result != 0)
            {
                return result;
            }
        }
        return len1 - len2;
    }
    }



Thanks for the help

Solution

  • var ordered = list.OrderByDescending(x => x.All(char.IsDigit))
     .ThenByDescending(x=> x.Any(char.IsLetter))
     .ThenBy(x=>x)
     .ToList();
    

    Result :

    1 
    2 
    r
    r1 
    r2 
    ' 
    @