System.Array. does not contain a definition for “ToList”

Question

I\'m getting the above error on the ToList() line of the code below

if (emailReplyTo != null)
{
  System.Collections.Generic.List replyto
    = ema         


        

Answer 1

In case someone stumbles on this questions after googling...

I had the exact same problem in Razor views and adding using System.Linq at the top didn't help.

What did help is calling .Cast() before using Linq extension methods:

myArrayVariable.Cast<SomeClass>().ToList() //ok, NOW ToList works fine

Answer 2

You can also do this without .toList, saves including an entire library for no real reason.

new List(array)

Answer 3

ToList() is an extension method. Maybe you're missing the

using System.Linq;

Answer 4

The ToList method you are looking for is an extension method. Try adding this using directive to the top of your file:

using System.Linq;

By adding this using directive you are indicating to the compiler that any extension methods in that namespace should be imported. It's kind of a shame that there isn't more help from Visual Studio around importing extension methods (ReSharper does this rather nicely).

Answer 5

This is simply because ArrayList does not expose a method named ToList.

See this MSDN page for a table view of the members available to you.

As explained by others, you may access this extension method by importing the Linq library:

using System.Linq;

Also, see this link for a custom implementation of such, should you desire to implement one.