You could use int.Parse and add the NumberStyles.AllowThousands flag:
int num = int.Parse(toParse, NumberStyles.AllowThousands);
Or int.TryParse letting you know if the operation succeeded:
int num;
if (int.TryParse(toParse, NumberStyles.AllowThousands,
CultureInfo.InvariantCulture, out num))
{
// parse successful, use 'num'
}