C# Find Duplicate Array Values

Here is a sample function which demonstrates the power of LINQ and C#

private Dictionary<int, int> GetArrayDuplicates(int[] arrayToSearch)
{
   Dictionary<int, int> counts = arrayToSearch.GroupBy(arrayItem => arrayItem)
      .ToDictionary(groupedItem => groupedItem.Key,
      groupedItem => groupedItem.Count());
   return counts;
}

Usage

int []array = { 10, 20, 30, 40, 50, 60 , 70, 80, 90, 100, 80, 40, 50, 100 };
Dictionary<int, int> counts = GetArrayDuplicates(array);