Question

I have a user control without a parameterless constructor; let’s call it WithoutDefaultConstructor. I want to insert a WithoutDefaultConstructor called myControl into the XAML code of another control (which is called MainWindow). However, I get this compiler error:

The type ‘WithoutDefaultConstructor’
cannot have a Name attribute. Value
types and types without a default
constructor can be used as items
within a ResourceDictionary.

How do I fix this without adding a parameterless constructor to WithoutDefaultConstructor?

Here are the contents of MainWindow.xaml:

<Window x:Class="WpfApplication1.MainWindow"
 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 xmlns:WpfApplication1="clr-namespace:WpfApplication1" Title="MainWindow" 
 Height="350" Width="525">
    <WpfApplication1:WithoutDefaultConstructor Name="myControl">
    </WpfApplication1:WithoutDefaultConstructor>
</Window>

Here are the contents of WithoutDefaultConstructor.xaml.cs:

using System.Windows.Controls;

namespace WpfApplication1
{
    public partial class WithoutDefaultConstructor : UserControl
    {
        private int I_really_need_to_initialize_this_int;

        public WithoutDefaultConstructor(int i)
        {
            InitializeComponent();
            I_really_need_to_initialize_this_int = i;
        }
    }
}

Answer 1

It’s not about the Name attribute. You just can’t create an instance of an object using constructor with parameter from XAML. There is a way to do it in XAML 2009, but it’s not available in code compiled to BAML, such as this.