c# - Is there a XAML equivalent to nameof? -


i'm working devexpress's wpf tree list view , came across think more general problem relating renaming properties on objects used item source. in tree list view 1 required specify parentfieldname , keyfieldname (which used determine structure of tree). these fields strings.

this has led issues refactoring code. example renaming property of objects using itemsource break tree view parentfieldname , keyfieldname no longer in sync property names. have worked around issue creating properties in view model "parentfieldname" , "keyfieldname" use nameof present property name view.

here cut down version of control:

    <usercontrol              xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"               xmlns:d="http://schemas.microsoft.com/expression/blend/2008"              xmlns:dxg="http://schemas.devexpress.com/winfx/2008/xaml/grid"                            d:designheight="300" d:designwidth="300">       <usercontrol.datacontext>           <viewmodel />       </usercontrol.datacontext>         <dxg:treelistcontrol autogeneratecolumns="addnew"                          enablesmartcolumnsgeneration="true" itemssource="{binding results}"                                                  selectionmode="row">             <dxg:treelistcontrol.view>                 <dxg:treelistview                                                                  parentfieldname="{binding parentidfieldname}" keyfieldname="{binding nodeidfieldname}"                                showhorizontallines="false" showverticallines="false"                               shownodeimages="true"/>             </dxg:treelistcontrol.view>         </dxg:treelistcontrol>     </usercontrol>

and viewmodel:

using devexpress.mvvm;      public sealed class viewmodel : viewmodelbase {     public string parentidfieldname => nameof(treenode.parentid);      public string nodeidfieldname => nameof(treenode.nodeid);      public observablecollection<treenode> results     {         => getproperty(() => results);         set => setproperty(() => results, value);     }  }

and tree node:

public sealed class treenode {     public int parentid {get; set;}     public int nodeid {get; set;} }

my solution works wondering if there better way of doing this. example, there can in xaml equivalent nameof call, rather binding parentidfieldname , nodeidfieldname in view model?

i realize described issue devexpress's control. i'm interested in whether approach i've used around can improved on. there way in more simple way directly in xaml?

i apologize in advance if code i've provided doesn't compile. i've cut down i'm working quite considerably provide example.

you can create custom markup extension.

for example:

[contentproperty(nameof(member))] public class nameofextension : markupextension {     public type type { get; set; }     public string member { get; set; }      public override object providevalue(iserviceprovider serviceprovider)     {         if (serviceprovider == null)             throw new argumentnullexception(nameof(serviceprovider));          if (type == null || string.isnullorempty(member) || member.contains("."))             throw new argumentexception("syntax x:nameof type={x:type [classname]} member=[propertyname]");          var pinfo = type.getruntimeproperties().firstordefault(pi => pi.name == member);         var finfo = type.getruntimefields().firstordefault(fi => fi.name == member);         if (pinfo == null && finfo == null)             throw new argumentexception($"no property or field found {member} in {type}");          return member;     } }

sample usage:

enter image description here


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