C# extensions method

Question

For such an extension:

public static class ImageExtensions
{
    public static Image LoadImage(string path)
    {
        using (MemoryStream ms = new MemoryStream(File.ReadAllBytes(path)))
            return Image.FromStream(ms);
    }
}

How to make it possible to be called Image.LoadImage(path) instead of ImageExtensions.LoadImage(path)?

I can normally use other extension methods, where their first parameter is this Image img. Those work by using instance.Method().

similar question with some more detailed answers: http://stackoverflow.com/questions/249222/can-i-add-extension-methods-to-an-existing-static-class — Kevin Nacios, Mar 07 '15 at 18:15

score 2 · Accepted Answer · answered Mar 07 '15 at 17:58

2

It is impossible. You cannot write extension methods that act as static extensions, because extensions methods require an object instance.

answered Mar 07 '15 at 17:58

user3711864

349
2
10

score 0 · Answer 2 · answered Mar 07 '15 at 18:33

Actually, a method with signature public static Image LoadImage(string path isn't even an extension. It is just a static method, therefore to write this as you would like it simply change the class name:

public static class Image
{
    public static Image LoadImage(string path)
    {
        using (MemoryStream ms = new MemoryStream(File.ReadAllBytes(path)))
            return Image.FromStream(ms);
    }
}

C# extensions method

2 Answers2