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c#wpfdata-binding

WPF password binding with passwordboxassistant through code

I'm trying to create a login screen but I want to do everything through code.

So generating the full UI through C#.

But I'm working with MVVM model and I have data binding on my username but this doesn't work on the standard PasswordBox so I found a namespace online which makes a workaround, it's called PasswordBoxAssistant from FunctionalFun.UI.

In the xaml I can create a passwordbox with the assistant but I'm making my UI through code and I'm not able to find how to use the PasswordBoxAssistant like that.

So I have this:

enter image description here

And want the same thing but in my C#:

enter image description here

But like you see in my code, I don't have access to it.

No idea if the xaml will only be to access it with everything is compile or why I can't use it in my C#.

Anybody that can help me implement this or point me to a direction?

Solution

  • It seems PasswordBoxAssistant is an attached property similar to PassWordHelper here:

    https://gist.github.com/alamsal/fcefce4fb2d2d70fb2d91ee12741a35f

    You attach such properties as described here:

    https://learn.microsoft.com/en-us/previous-versions/dotnet/netframework-4.0/ms749011(v=vs.100)#attached-properties-in-code

    Hence something like

     PasswordBoxAssistant.SetBindPassword(yourPasswordBox, true);

    Would add that to a variable yourPasswordBox.

    You then need to create a binding on the BoundPassword dependency property of course.

    https://learn.microsoft.com/en-us/dotnet/desktop/wpf/data/how-to-create-a-binding-in-code?view=netframeworkdesktop-4.8

    The property you are binding as target is the PasswordBoxAssistant dependency property.

    Bindings are a bit fiddly in code. I have used the approach rarely.

    A rough example:

    Binding myBinding = new Binding();
// myBinding.Source = ViewModel; Datacontext is default, you probably don't need source.
myBinding.Path = new PropertyPath("SomeStringPropertyInDatacontext");
myBinding.Mode = BindingMode.TwoWay;
myBinding.UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged;
yourPasswordBox.SetBinding(PasswordBoxAssistant.BoundPasswordProperty, myBinding);