How to bind a property from my usercontrol content control to a property in my viewmodel?

Question

I have a usercontrol like this:

<UserControl x:Class="MySample.customtextbox"

         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" 

         mc:Ignorable="d" 

         d:DesignHeight="20" d:DesignWidth="300">

    <Grid>

           <TextBox x:Name="Ytextbox"  Background="Yellow"/> 

    </Grid>

</UserControl>

I want use this control in a View such as MainWindowView
How can I Binde my Ytextbox Text Property to a property in my MainWindowViewModel?

<CT:customtextbox  Text="{binding  mypropertyinviewmodel}"/>

I know that I must define a

DependencyProperty

for my control until I can bind a property in my viewmodel to it so i define a dependency property for my control like this:

public static readonly DependencyProperty InfoTextProperty = 

        DependencyProperty.Register("InfoText", typeof(string), typeof(customtextbox), new FrameworkPropertyMetadata(false));



public string InfoText

{

    get { return (string)GetValue(InfoTextProperty);}

    set

    {

        SetValue(InfoTextProperty, value); 

    }

}

When I define a dependency property for my control I have a xaml error:

Error 1 Cannot create an instance of "customtextbox".

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Answer 1

new FrameworkPropertyMetadata(false)

You cannot set the default value of a string property to false (which of course is a bool).

There may be some other problems (e.g. you have no binding on the TextBox in the user coontrol declaration and you try to set a property you did not register where you create an instance) but for those you should search SO.

How to bind a property from my usercontrol content control to a property in my viewmodel?

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