I'm trying to combine List<string> strings using string.Join(",", strings) but everything I'm reading says I should do:
List<string> strings
string.Join(",", strings)
string.Join(",", strings.ToArray())
Is there a certain reason I have to/should use .ToArray()?
.ToArray()
Probably because everything you're reading was written for an earlier version of the framework. The string.Join(string, IEnumerable<string>) method was added in version 4.
string.Join(string, IEnumerable<string>)