c#拼接List

记录下c#中拼接字符串

string fileids = string.Empty;

List<string> list=new List<string>();

list.add("1");

list.add("2");

list.add("2");

list.add("4");

fileids = string.Join(",", list.ToArray());

fileids应为：1,2,3,4

string.Join(string separator,params objects[] values);

返回字符串数组包含此实例的子字符串

filesids.Trim(',');

string[] Id = listids.Split(',');