I have a COM function that expects object[]
as a parameter:
foo(object[] values)
I want to pass some enum
fields to it so I use the following:
object[] fields = (object[])Enum.GetValues(typeof(SomeEnumType));
However, when I try to pass fields
to foo(...)
ie [ foo(fields)
] I get an error:
"Unable to cast object of type `SomeEnumType[]' to type 'system.Object[]'.
Can anyone tell me what I'm doing wrong?
As the exception says, you can't convert cast a SomeEnumType[]
to object[]
- the former is an array where each value is a SomeEnumType
value; the latter is an array where each element is a reference.
With LINQ you can create a new array easily enough:
object[] fields = Enum.GetValues(typeof(SomeEnumType))
.Cast<object>()
.ToArray();
This will basically box each element (each enum value) to create an IEnumerable<object>
, then create an array from that. It's similar to Tilak's approach, but I prefer to use Cast
when I don't actually need a general-purpose projection.
Alternatively:
SomeEnumType[] values = (SomeEnumType[]) Enum.GetValues(typeof(SomeEnumType));
object[] fields = Array.ConvertAll(values, x => (object) x);
Enum.GetValues(typeof(SomeEnumType)).Cast<object>().ToArray()
You need to cast the proper array type. Try something along these lines:
object[] fields = (object[])Enum.GetValues(typeof(SomeEnumType)).Cast<object>().ToArray();
The error message is stating that the function is expecting an object array of type "object" and you're passing in one of type "SomeEnumType", so there is a type mismatch.
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