LINQ Bug ? Get a string array from a list of long

Question

I'm getting this Unable to cast object of type 'System.Int64' to type 'System.String'. from following code snippet:

 IList<long> Ids = new List<long>();
 Ids.Add(6962056);
 Ids.Add(7117210);
 Ids.Add(13489241);

 var stringIds = Ids.Cast<string>().ToArray();

and Booooooooooooom .... ideas ?

Answer 1

You cannot cast a long to a string. You need to specify what operation to perform to turn the longs into strings. I prefer using Linq to select out the new values:

var stringIds = Ids.Select(id => id.ToString());

Answer 2

Thats because you can not cast longs to strings.

You're confusing

long l = 10;
string s = (string)l; // this will not work, l is not a string

with

long l = 10;
string s = l.ToString(); // this will work