How to make Resharper resolve path for CustomBinding MarkupExtension

Question

I want to create some extended Binding-Markup-Extension, which behaves just like a normal WPF-Binding but does some things more (use different defaults, maybe add some behavior,

Answer 1

One way to fool R# is to name it Binding:

public class Binding : MarkupExtension
{
    public Binding()
    {
    }

    public Binding(string path)
    {
        Path = path;
    }

    public string Path { get; set; }

    public override object ProvideValue(IServiceProvider serviceProvider)
    {
        return 5;
    }
}

Then it works the same as standard binding with R#

<TextBlock Text="{custom:Binding SomeProp}" />

Answer 2

You should access your custom Markup-Extension, using the correct namespace:

<UserControl x:Name="uc" ...
xmlns:ext="clr-ns:YourProjectNamespace">
  <TextBox Text="{ext:CustomBinding ViewModel.CurrentText, ElementName=uc}" />
</UserControl>

Here is a nice article about creating custom Markup-Extensions.

Answer 3

Actually it's not possible in current versions of R# and, unfortunately, still be missing feature of upcoming R# 6.1 release.

This feature requires a lot of infrastructure changes, but it's on our list and definitely will be implemented in R# 7. Seems like [CustomBindingMarkup] and [BindingPath] (for path constructor parameter and the Path property) attributes will be introduced.

We really apologize for any inconvenience.