扩展 ImageMagickNet

Question

我正在尝试向 ImageMagickNet 类添加自定义函数。它应该使用 ImageMagick.NET 项目中的 IsSimilarImage magick 方法，但我很困惑是否必须通过 Magick++ 路由此方法，因为 .NET 端可用的任何功能都源自魔法++。

Answer 1

这已经很老了，但由于尚未得到答复，所以就到这里。

请注意，我没有查看过 ImageMagick 库，因此下面代码中的任何实现细节都只是一个示例。用正确的实施取代垃圾。假设它正在导出有效的 .NET 对象，那么它的工作方式如下：

' Put your extension methods or properties in a clearly labeled module file, on its own within your project
Module ImageMagickNetExtensions

    ' Define an extension method by using the ExtensionAttribute, and make the first argument
    ' for the method the type that you wish to extend. This will serve as a reference to the extended
    ' instance, so that you can reference other methods and properties within your extension code.
    <Extension()> _
    Public Function SomeExtensionFunction(ByVal imn As ImageMagickNet, ByVal filename As String) As Boolean
        Return imn.IsSimilarImage(filename)
    End Function

End Module

Class SomeClass
    ' To use your extension method within your project containing the extension module, simply
    ' call it on any valid instance of the type you have extended. The compiler will call your code
    ' whenever it sees reference to it, passing a reference to your extended instance.
    Private imn As New ImageMagickNet

    Private Sub DoSomething()
        If imn.SomeExtensionFunction("c:\someimage.jpg") Then
            ...
        End If
    End Sub
End Class