可能是不存储重复元素的hashset，它会默默地忽略添加请求 重复。

static void Main()
{
    string textWithDuplicates = "aaabbcccggg";     

    Console.WriteLine(textWithDuplicates.Count());  
    var letters = new HashSet<char>(textWithDuplicates);
    Console.WriteLine(letters.Count());

    foreach (char c in letters) Console.Write(c);
    Console.WriteLine("");

    int[] array = new int[] { 12, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2 };

    Console.WriteLine(array.Count());
    var distinctArray = new HashSet<int>(array);
    Console.WriteLine(distinctArray.Count());

    foreach (int i in distinctArray) Console.Write(i + ",");
}

——这是面试中每次都会问的问题。现在我完成了它的编码。

static void Main(string[] args)
{    
            int[] array = new int[] { 4, 8, 4, 1, 1, 4, 8 };            
            int numDups = 0, prevIndex = 0;

            for (int i = 0; i < array.Length; i++)
            {
                bool foundDup = false;
                for (int j = 0; j < i; j++)
                {
                    if (array[i] == array[j])
                    {
                        foundDup = true;
                        numDups++; // Increment means Count for Duplicate found in array.
                        break;
                    }                    
                }

                if (foundDup == false)
                {
                    array[prevIndex] = array[i];
                    prevIndex++;
                }
            }

            // Just Duplicate records replce by zero.
            for (int k = 1; k <= numDups; k++)
            {               
                array[array.Length - k] = '\0';             
            }


            Console.WriteLine("Console program for Remove duplicates from array.");
            Console.Read();
        }

注意:未测试!

string[] test(string[] myStringArray)
{
    List<String> myStringList = new List<string>();
    foreach (string s in myStringArray)
    {
        if (!myStringList.Contains(s))
        {
            myStringList.Add(s);
        }
    }
    return myStringList.ToString();
}

也许能满足你的需要…

编辑啊! !不到一分钟就被抢了!

在下面找到答案。

class Program
{
    static void Main(string[] args)
    {
        var nums = new int[] { 1, 4, 3, 3, 3, 5, 5, 7, 7, 7, 7, 9, 9, 9 };
        var result = removeDuplicates(nums);
        foreach (var item in result)
        {
            Console.WriteLine(item);
        }
    }
    static int[] removeDuplicates(int[] nums)
    {
        nums = nums.ToList().OrderBy(c => c).ToArray();
        int j = 1;
        int i = 0;
        int stop = 0;
        while (j < nums.Length)
        {
            if (nums[i] != nums[j])
            {
                nums[i + 1] = nums[j];
                stop = i + 2;
                i++;
            }
            j++;
        }
        nums = nums.Take(stop).ToArray();
        return nums;
    }
}

这是基于我刚刚解决的一个测试的一点贡献，可能对这里其他顶级贡献者的改进有所帮助。 以下是我所做的事情:

I used OrderBy which allows me order or sort the items from smallest to the highest using LINQ I then convert it to back to an array and then re-assign it back to the primary datasource So i then initialize j which is my right hand side of the array to be 1 and i which is my left hand side of the array to be 0, i also initialize where i would i to stop to be 0. I used a while loop to increment through the array by going from one position to the other left to right, for each increment the stop position is the current value of i + 2 which i will use later to truncate the duplicates from the array. I then increment by moving from left to right from the if statement and from right to right outside of the if statement until i iterate through the entire values of the array. I then pick from the first element to the stop position which becomes the last i index plus 2. that way i am able to remove all the duplicate items from the int array. which is then reassigned.

protected void Page_Load(object sender, EventArgs e)
{
    string a = "a;b;c;d;e;v";
    string[] b = a.Split(';');
    string[] c = b.Distinct().ToArray();

    if (b.Length != c.Length)
    {
        for (int i = 0; i < b.Length; i++)
        {
            try
            {
                if (b[i].ToString() != c[i].ToString())
                {
                    Response.Write("Found duplicate " + b[i].ToString());
                    return;
                }
            }
            catch (Exception ex)
            {
                Response.Write("Found duplicate " + b[i].ToString());
                return;
            }
        }              
    }
    else
    {
        Response.Write("No duplicate ");
    }
}

你可以使用一个LINQ查询来做到这一点:

int[] s = { 1, 2, 3, 3, 4};
int[] q = s.Distinct().ToArray();