How to use C# in Excel to convert string array to List<int>

[lilyed72]

how would i use C# in excel to convert string array to List<int>

string strIDs = "15|20|30";
List<int> IDs = strIDs.Split('|').Cast<int>().ToList();

the above code gives error "Specified cast is not valid."

[iceblue support]

string strIDs = "15|20|30";
List<int> IDs;
string[] strArr = strIDs.Split('|');
int[] intArr = Array.ConvertAll<string, int>(strArr, new Converter<string, int>(Convert.ToInt32));
IDs = intArr.ToList();