c#linq orderby是字符串的数字(你不能将它们转换为int)

时间:2011-06-18 13:33:48

标签: c# linq

我正在尝试对字符串数组进行排序,我希望它们按数字排序。

问题在于我无法将数字转换为int

以下是代码:

string[] things= new string[] { "105", "101", "102", "103", "90" };

foreach (var thing in things.OrderBy(x => x))
{
    Console.WriteLine(thing);
}

输出:101,102,103,105,90

我想:90,101,102,103,105

编辑: 输出不能是090,101,102 ......

将代码示例更新为“thing”而不是“sizes”。数组可以是这样的:

string[] things= new string[] { "paul", "bob", "lauren", "007", "90" };

这意味着它需要按字母顺序和数字排序:

007,90,bob,lauren,paul

19 个答案:

答案 0 :(得分:90)

将自定义比较器传递给OrderBy。 Enumerable.OrderBy将允许您指定您喜欢的任何比较器。

这是一种方法:

void Main()
{
    string[] things= new string[] { "paul", "bob", "lauren", "007", "90", "101"};

    foreach (var thing in things.OrderBy(x => x, new SemiNumericComparer()))
    {    
        Console.WriteLine(thing);
    }
}


public class SemiNumericComparer: IComparer<string>
{
    public int Compare(string s1, string s2)
    {
        if (IsNumeric(s1) && IsNumeric(s2))
        {
            if (Convert.ToInt32(s1) > Convert.ToInt32(s2)) return 1;
            if (Convert.ToInt32(s1) < Convert.ToInt32(s2)) return -1;
            if (Convert.ToInt32(s1) == Convert.ToInt32(s2)) return 0;
        }

        if (IsNumeric(s1) && !IsNumeric(s2))
            return -1;

        if (!IsNumeric(s1) && IsNumeric(s2))
            return 1;

        return string.Compare(s1, s2, true);
    }

    public static bool IsNumeric(object value)
    {
        try {
            int i = Convert.ToInt32(value.ToString());
            return true; 
        }
        catch (FormatException) {
            return false;
        }
    }
}

答案 1 :(得分:79)

用零填充到相同的长度:

int maxlen = sizes.Max(x => x.Length);
sizes.OrderBy(x => x.PadLeft(maxlen, '0'));

答案 2 :(得分:67)

而且,这个怎么样......

string[] sizes = new string[] { "105", "101", "102", "103", "90" };

var size = from x in sizes
           orderby x.Length, x
           select x;

foreach (var p in size)
{
    Console.WriteLine(p);
}

答案 3 :(得分:44)

值是一个字符串

List = List.OrderBy(c => c.Value.Length).ThenBy(c => c.Value).ToList();

作品

答案 4 :(得分:4)

我想如果它在字符串中有一些数字会更好。 希望它会有所帮助。

PS:我不确定性能或复杂的字符串值,但它的效果很好:

lorem ipsum
lorem ipsum 1
lorem ipsum 2
lorem ipsum 3
...
lorem ipsum 20
lorem ipsum 21

public class SemiNumericComparer : IComparer<string>
{
    public int Compare(string s1, string s2)
    {
        int s1r, s2r;
        var s1n = IsNumeric(s1, out s1r);
        var s2n = IsNumeric(s2, out s2r);

        if (s1n && s2n) return s1r - s2r;
        else if (s1n) return -1;
        else if (s2n) return 1;

        var num1 = Regex.Match(s1, @"\d+$");
        var num2 = Regex.Match(s2, @"\d+$");

        var onlyString1 = s1.Remove(num1.Index, num1.Length);
        var onlyString2 = s2.Remove(num2.Index, num2.Length);

        if (onlyString1 == onlyString2)
        {
            if (num1.Success && num2.Success) return Convert.ToInt32(num1.Value) - Convert.ToInt32(num2.Value);
            else if (num1.Success) return 1;
            else if (num2.Success) return -1;
        }

        return string.Compare(s1, s2, true);
    }

    public bool IsNumeric(string value, out int result)
    {
        return int.TryParse(value, out result);
    }
}

答案 5 :(得分:4)

您说您无法将数字转换为int,因为数组可以包含无法转换为int的元素,但尝试时没有任何害处:

string[] things = new string[] { "105", "101", "102", "103", "90", "paul", "bob", "lauren", "007", "90" };
Array.Sort(things, CompareThings);

foreach (var thing in things)
    Debug.WriteLine(thing);

然后比较如下:

private static int CompareThings(string x, string y)
{
    int intX, intY;
    if (int.TryParse(x, out intX) && int.TryParse(y, out intY))
        return intX.CompareTo(intY);

    return x.CompareTo(y);
}

输出:007,90,90,101,102,103,105,鲍勃,劳伦,保罗

答案 6 :(得分:4)

试试这个

sizes.OrderBy(x => Convert.ToInt32(x)).ToList<string>();

注意: 当所有字符串都可以转换为int .....时,这将很有用。

答案 7 :(得分:3)

这似乎是一个奇怪的请求,值得一个奇怪的解决方案:

string[] sizes = new string[] { "105", "101", "102", "103", "90" };

foreach (var size in sizes.OrderBy(x => {
    double sum = 0;
    int position = 0;
    foreach (char c in x.ToCharArray().Reverse()) {
        sum += (c - 48) * (int)(Math.Pow(10,position));
        position++;
    }
    return sum;
}))

{
    Console.WriteLine(size);
}

答案 8 :(得分:2)

该网站讨论了字母数字排序,并将逻辑意义上的数字排序,而不是ASCII感。它还考虑了它周围的alphas:

http://www.dotnetperls.com/alphanumeric-sorting

示例:

  • C:/TestB/333.jpg
  • 11
  • C:/TestB/33.jpg
  • 1
  • C:/TestA/111.jpg
  • 111F
  • C:/TestA/11.jpg
  • 2
  • C:/TestA/1.jpg
  • 111D
  • 22
  • 111Z
  • C:/TestB/03.jpg

  • 1
  • 2
  • 11
  • 22
  • 111D
  • 111F
  • 111Z
  • C:/TestA/1.jpg
  • C:/TestA/11.jpg
  • C:/TestA/111.jpg
  • C:/TestB/03.jpg
  • C:/TestB/33.jpg
  • C:/TestB/333.jpg

代码如下:

class Program
{
    static void Main(string[] args)
    {
        var arr = new string[]
        {
           "C:/TestB/333.jpg",
           "11",
           "C:/TestB/33.jpg",
           "1",
           "C:/TestA/111.jpg",
           "111F",
           "C:/TestA/11.jpg",
           "2",
           "C:/TestA/1.jpg",
           "111D",
           "22",
           "111Z",
           "C:/TestB/03.jpg"
        };
        Array.Sort(arr, new AlphaNumericComparer());
        foreach(var e in arr) {
            Console.WriteLine(e);
        }
    }
}

public class AlphaNumericComparer : IComparer
{
    public int Compare(object x, object y)
    {
        string s1 = x as string;
        if (s1 == null)
        {
            return 0;
        }
        string s2 = y as string;
        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(space1[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;
    }
}

答案 9 :(得分:2)

Jeff Paulsen给出的答案是正确的,但Comprarer可以简化为:

public class SemiNumericComparer: IComparer<string>
{
    public int Compare(string s1, string s2)
    {
        if (IsNumeric(s1) && IsNumeric(s2))
          return Convert.ToInt32(s1) - Convert.ToInt32(s2)

        if (IsNumeric(s1) && !IsNumeric(s2))
            return -1;

        if (!IsNumeric(s1) && IsNumeric(s2))
            return 1;

        return string.Compare(s1, s2, true);
    }

    public static bool IsNumeric(object value)
    {
        int result;
        return Int32.TryParse(value, out result);
    }
}

这是有效的,因为唯一检查Comparer结果的是结果是大于,小于还是等于零。可以简单地从另一个值中减去这些值,而不必处理返回值。

同样,IsNumeric方法不必使用try - 块,并且可以从TryParse中受益。

对于那些不确定的人: 此Comparer将对值进行排序,以便非数值始终附加到列表的末尾。如果在开始时想要它们,则必须交换第二个和第三个if块。

答案 10 :(得分:1)

试试这个:

string[] things= new string[] { "105", "101", "102", "103", "90" };

int tmpNumber;

foreach (var thing in (things.Where(xx => int.TryParse(xx, out tmpNumber)).OrderBy(xx =>     int.Parse(xx))).Concat(things.Where(xx => !int.TryParse(xx, out tmpNumber)).OrderBy(xx => xx)))
{
    Console.WriteLine(thing);
}

答案 11 :(得分:1)

public class NaturalSort: IComparer<string>
{
          [DllImport("shlwapi.dll", CharSet = CharSet.Unicode)]
          public static extern int StrCmpLogicalW(string x, string y);

          public int Compare(string x, string y)
          {
                 return StrCmpLogicalW(x, y);
          }
}

arr = arr.OrderBy(x =&gt; x,new NaturalSort())。ToArray();

我需要它的原因是归档到一个文件名以数字开头的目录:

public static FileInfo[] GetFiles(string path)
{
  return new DirectoryInfo(path).GetFiles()
                                .OrderBy(x => x.Name, new NaturalSort())
                                .ToArray();
}

答案 12 :(得分:0)

我的首选解决方案(如果所有字符串都只是数字):

set.seed(1)
X <- matrix(runif(100*200),nrow=100)
X <- apply(X,1,sort)
lattice::levelplot(X,contour=TRUE)

library(raster)
r <- raster(X)
z <- cut(r, seq(0, 1, 0.1))
p <- rasterToPolygons(z, dissolve=TRUE)
spplot(p)

答案 13 :(得分:0)

public class Test
{
    public void TestMethod()
    {
        List<string> buyersList = new List<string>() { "5", "10", "1", "str", "3", "string" };
        List<string> soretedBuyersList = null;

        soretedBuyersList = new List<string>(SortedList(buyersList));
    }

    public List<string> SortedList(List<string> unsoredList)
    {
        return unsoredList.OrderBy(o => o, new SortNumericComparer()).ToList();
    }
}

   public class SortNumericComparer : IComparer<string>
{
    public int Compare(string x, string y)
    {
        int xInt = 0;
        int yInt = 0;
        int result = -1;

        if (!int.TryParse(x, out xInt))
        {
            result = 1;
        }

        if(int.TryParse(y, out yInt))
        {
            if(result == -1)
            {
                result = xInt - yInt;
            }
        }
        else if(result == 1)
        {
             result = string.Compare(x, y, true);
        }

        return result;
    }
}

答案 14 :(得分:0)

Try this out..  



  string[] things = new string[] { "paul", "bob", "lauren", "007", "90", "-10" };

        List<int> num = new List<int>();
        List<string> str = new List<string>();
        for (int i = 0; i < things.Count(); i++)
        {

            int result;
            if (int.TryParse(things[i], out result))
            {
                num.Add(result);
            }
            else
            {
                str.Add(things[i]);
            }


        }

现在对列表进行排序并将它们合并回来......

        var strsort = from s in str
                      orderby s.Length
                      select s;

        var numsort = from n in num
                     orderby n
                     select n;

        for (int i = 0; i < things.Count(); i++)
        {

         if(i < numsort.Count())
             things[i] = numsort.ElementAt(i).ToString();
             else
             things[i] = strsort.ElementAt(i - numsort.Count());               
               }

我只是想在这个有趣的问题上做出贡献......

答案 15 :(得分:0)

扩大Jeff Paulsen的答案。我想确保字符串中有多少个数字或字符组都没关系:

reduce

在修改SO Page以处理文件名之后,我还从here中获取了SplitCharsAndNums。

答案 16 :(得分:0)

简短的 IComparer 类示例。

  1. 如果两个字符串参数都可以转换为整数,则参数 被解析为整数并进行比较
  2. 如果只有一个参数可以转换为整数,那么整数就是 优先级(具有较低的值)并在字符串之前插入。
  3. 如果没有一个参数可以转换为整数,那么普通 使用字符串比较。

代码:

public class CompareIntegerStrings : IComparer<string>
    {
        public int Compare(string x, string y)
        {
            if (int.TryParse(x, out int xOut) && int.TryParse(y, out int yOut))
                return xOut.CompareTo(yOut);
            else if (int.TryParse(x, out _))
                return -1;
            else if (int.TryParse(y, out _))
                return 1;
            else
                return x.CompareTo(y);
    
        }
    }

在这个例子中

List<string> intStrings = new List<string> { "01","0022","abba", "11", "deep purple", "02", };
List<string> orderedIntStrings = intStrings.OrderBy(i=>i,new CompareIntegerStrings()).ToList();

有序列表orderedIntString是{"01","02","11","0022","abba","deep Purple"}。

答案 17 :(得分:-1)

尽管这是一个老问题,但我想提出一个解决方案:

string[] things= new string[] { "105", "101", "102", "103", "90" };

foreach (var thing in things.OrderBy(x => Int32.Parse(x) )
{
    Console.WriteLine(thing);
}
Woha很简单吧? :d

答案 18 :(得分:-1)

namespace X
{
    public class Utils
    {
        public class StrCmpLogicalComparer : IComparer<Projects.Sample>
        {
            [DllImport("Shlwapi.dll", CharSet = CharSet.Unicode)]
            private static extern int StrCmpLogicalW(string x, string y);


            public int Compare(Projects.Sample x, Projects.Sample y)
            {
                string[] ls1 = x.sample_name.Split("_");
                string[] ls2 = y.sample_name.Split("_");
                string s1 = ls1[0];
                string s2 = ls2[0];
                return StrCmpLogicalW(s1, s2);
            }
        }

    }
}