Convert ArrayList to ArrayConvert an ArrayList to an array. Invoke the ToArray Function.
This page was last reviewed on Sep 24, 2022.
Convert ArrayList, Array. In VB.NET an ArrayList can be converted to an array. This is possible with the ToArray Function. With it we get an Object array from an ArrayList.
Function info. ToArray is useful—it is not the same as the ToArray extension from System.Linq. We can perform the conversion with just one line of code.
To start, we create an ArrayList. All the elements in the ArrayList are of type String. This is important—when we call ToArray, we get an Object array, not a String array.
However When we loop through the Object array, we can cast each element to a String.
Object Array
Note We can not directly cast the array to a String(). This exception is reported.
Module Module1 Sub Main() ' Create ArrayList. Dim list As ArrayList = New ArrayList() list.Add("Dot") list.Add("Net") list.Add("Perls") ' Get array of objects. Dim array() As Object = list.ToArray() For Each element In array ' Cast object to string. Dim value As String = element Console.WriteLine(value) Next End Sub End Module
Dot Net Perls
Unhandled Exception: System.InvalidCastException: Unable to cast object of type 'System.Object[]' to type 'System.String[]'.
Discussion. The ArrayList makes converting your collection to an array more difficult. If you use the List type, you can convert to a typed array such as String(). This results in clearer code.
Summary. We used the ToArray function on the ArrayList type to convert an ArrayList to an Object() array. We looked at the exception that is thrown when you try to cast the result array.
Dot Net Perls is a collection of tested code examples. Pages are continually updated to stay current, with code correctness a top priority.
Sam Allen is passionate about computer languages. In the past, his work has been recommended by Apple and Microsoft and he has studied computers at a selective university in the United States.
This page was last updated on Sep 24, 2022 (edit).
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