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POHow can I edit immutable objects in WPF without duplicating code?
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copied!<p>We have lots of immutable value objects in our domain model, one example of this is a position, defined by a latitude, longitude & height.</p> <pre><code>/// <remarks>When I grow up I want to be an F# record.</remarks> public class Position { public double Latitude { get; private set; } // snip public Position(double latitude, double longitude, double height) { Latitude = latitude; // snip } } </code></pre> <p>The obvious way to allow editing of a position is to build a ViewModel which has getters <em>and</em> setters, as well as a ToPosition() method to extract the validated immutable position instance. While this solution would be ok, it would result in a lot of duplicated code, especially XAML.</p> <p>The value objects in question consist of between three and five properties which are usually some variant of X, Y, Z & some auxiliary stuff. Given this, I had considered creating three ViewModels to handle the various possibilities, where each ViewModel would need to expose properties for the value of each property as well as a description to display for each label (eg. "Latitude").</p> <p>Going further, it seems like I could simplify it to one general ViewModel that can deal with N properties and hook everything up using reflection. Something like a property grid, but for immutable objects. One issue with a property grid is that I want to be able to change the look so I can have labels and textboxes such as:</p> <pre><code>Latitude: [ 32 ] <- TextBox Longitude: [ 115 ] Height: [ 12 ] </code></pre> <p>Or put it in a DataGrid such as:</p> <pre><code>Latitude | Longitude | Height 32 115 12 </code></pre> <p><em>So my question is:</em></p> <p>Can you think of an elegant way to solve this problem? Are there any libraries that do this or articles about something similar?</p> <p>I'm mainly looking for:</p> <ul> <li>Code duplication to be minimized</li> <li>Easy to add new value object types</li> <li>Possible to extend with some kind of validation</li> </ul>

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