.net - Extending Sealed Intrinsic Datatypes Using CompilerServices.Extensions-No Way To Reuse?
Nov 11, 2010
I defined the following extension of the Date? data type
[Code]...
But when I moved my compiler definition to a separate DLL, I the ToObject method was no longer available from my project even though I had referenced the Class project which now contained the extension. Is this a limitation of the Compiler Extensions? HOw do you get reusability out of them?
Briefly, what I'm trying to do is add some methods and properties to the FileInfo class, which is sealed (NotInheritable). As far as I can tell, I have two options to do this.
1) Inherit from FileSystemInfo (the base class for FileInfo) and recreate the methods and properties added by FileInfo (essentially recreating the FileInfo class from scratch)
2) Use extension methods (??) which I just learned about two minutes ago and it being 1am, I'm going to get into this tomorrow
3) Create a wrapper class around a FileInfo object - I think that's the proper term
Ok, so I guess there are 3 options.
A) Why make a class uninheritable
B) Is creating a wrapper class "basically" the same as inheriting from an object, but at least with inheritence you don't need to create any properties and methods other than those you want to modify or add?
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Type 'Microsoft.VisualBasic.CompilerServices.DesignerGenerated' is not defined.
The error comes from the auto-generated code in MainWindow.g.i.vb - when I try to add a reference to Microsoft.VisualBasic, it says I can't because it will be added at runtime.
I've read that making a class sealed in C# is advisable in high-performance scenarios because it frees the compiler to make certain optimizations (e.g., inlining property getters) that it wouldn't be able to make otherwise. Is the same true for NotInheritable in VB.NET?
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Public Sub AddSetting(ByVal PropertyName As String, ByVal PropertyType As Type, ByVal DefaultValue As String) Dim p As New SettingsProperty(PropertyName) p.PropertyType = PropertyType p.DefaultValue = DefaultValue [Code] .....
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Here is my code:
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