将Int数组转换为Enum标志

Question

I have the following enum with flags:

[Flags]
public enum DataFiat {
  Public = 1,
  Listed = 2,
  Client = 4
} // DataFiat

And I have an int array, for example:

int[] selected = new int[] { 1, 4 }

How can I convert this to my enum which would become:

DataFiat.Public | DataFiat.Client

Thank You, Miguel

Answer 1

var f = (DataFiat)selected.Sum();

Answer 2

怎么样的

var tt = (DataFiat)selected.Aggregate((i, t) => i | t);

Answer 3

this snippet:

        var intArr = new[] { 1, 4 };
        var sum = intArr.Sum(x => x);
        var result = (Test)sum;

returns

Answer 4

DataFlat result = (DataFlat) 0;

foreach (var value in selected)
{
    result |= (DataFlat)value;
}

Or if you want to use LINQ

DataFlat result = (DataFlat) selected.Aggregate(0, (old, current) => old | current);

Answer 5

You mean this?

IEnumerable<DataFiat> selectedDataFiats = selected.Cast<DataFiat>();

This sinmply casts each int to DataFiat .

Answer 6

You can't just cast the array, if it's really an object[]. You can create a new array pretty easily though:

var enumArray = originalArray.Cast<DataFiat>().ToArray();

If it were actually an int[] array to start with, you could cast - although you'd have to talk nicely to the C# compiler first:

using System;

class Program
{
    enum Foo
    {
        Bar = 1,
        Baz = 2
    }

    static void Main()
    {
        int[] ints = new int[] { 1, 2 };
        Foo[] foos = (Foo[]) (object) ints;
        foreach (var foo in foos)
        {
            Console.WriteLine(foo);
        }
    }
}

The C# compiler doesn't believe that there's a conversion from int[] to Foo[] (and there isn't, within the rules of C#)... but the CLR is fine with this conversion, so as long as you can persuade the C# compiler to play along (by casting to object first) it's fine.

This doesn't work when the original array is really an object[] though.

Hope this helps..