I have dictionary code as follows:

```
int entry=0;
string[] numbers ={"123","123","123","456","123"};
Dictionary<string, List<string>> dictionary = new Dictionary<string, List<string>>();
foreach (string number in numbers)
{
    if (dictionary.ContainsKey("ABC"))
    {

    }
    else if (!dictionary.ContainsKey("ABC") && entry==0)
    {
        dictionary.Add("ABC", new List<string>());
        dictionary["ABC"].Add(number);
        entry = 1;
    }
    else if (!dictionary.ContainsKey("ABC") && entry == 1)
    {
        dictionary["ABC"].Add(number);
    }
}
foreach(KeyValuePair<string,string> kvp in dictionary)
{
    Console.WriteLine("Key={0},Value = {1}", kvp.Key,kvp.Value);
}
Console.ReadKey();

```

I want output like as follows `Key="ABC",Value="123,456"` i.e. I need to print all the dictionary values only once without repeat. In above string array 123 came 4 times.But I want to print that only one time and need 456 also and also joint that values with comma(",").So I need output like `Key="ABC",Value="123,456"`. Please share your ideas. Thanks in advance.