I'm trying to call a method but it's telling me that I need to pass in an array. There is no Convert.ToArray() method, and casting doesn't work.
How can I convert a list to an array?
4 Answers
You shouldn't use Arraylists (your question is tagged arraylist) in the first place. They are deprecated as of C# 2 and generics (Use List<int> for dynamically sized collection of integers for example). Then, if you have C# 3.5 and later you should use the aforementioned .ToArray() extension method. And if you don't have the latest and greatest C#, you can use
ArrayList arraylist= new ArrayList();
arraylist.Add( 1 );
arraylist.Add( 2 );
arraylist.Add( 3 );
int[] mydatas = (int[]) arraylist.ToArray(typeof(int));
Comments
You can with System.Linq.Enumerable.ToArray:
using System.Linq;
...
var b = a.ToArray();
2 Comments
Lonnie Schultz
I tried that, but it gave me an error: "The type or namespace name 'Linq' does not exist in the namespace 'System'." Should it be "Link"?
Gleno
@Lonnie You'll get this error if you don't reference "System.Core.dll"
Call the ToArray() method on your list object. I have provided a link to the documentation.
This documentation refers to the System.Collections.Generic namespace which is available in all versions of .NET unlike the more specialized linq namespace. They do perform the same function, however no details on performance comparisons are provided here.
MSDN documentation on List.ToArray Method
Namespace: System.Collections.Generic
Assembly: mscorlib (in mscorlib.dll)
public T[] ToArray()
Comments
Try
yourList.ToArray()
is part of the Enumerable extension methods
