convert List<string> to 1,2,3,4,5

[jataz2]

string[] arryID = {"1", "2", "3", "4","5","6","7","8","9"};
List<string> lstID = arryID .ToList();

string input_id = string.Join(",", lstID .Select(d => d.ToString()).ToList());

ตัวแปร input_id จะมีค่าดังต่อไปนี้ : "1", "2", "3", "4","5","6","7","8","9"