How can I handle this cast exception in C# : system.data.model in system.windows.controls.CheckBox?

Question

This is my model class of analys

public partial class analys
    {
        public int id { get; set; }
        public string name { get; set; }
        public int price { get; set; }
        public bool Type_qualitatif { get; set; }
        public bool Type_quantitatif { get; set; }
        public System.DateTime create_at { get; set; }
        public System.DateTime update_at { get; set; }
        public int sectionId { get; set; }
    
        public virtual section section { get; set; }
    }
}

I create a ListBox which display checkboxes as items, and the content of each one is the name of an analys.

So I am trying to get the content of the checkboxes checked and save them in a list with the code bellow

foreach ( CheckBox item in  _biochimieExam.BiochimieExamsItemsControl.Items )
             {
                 if(item.IsChecked == true)
                 {
                   //  String exam = item.Content.ToString();
                     SelctedItems.Add(item.Content.ToString());
                 }
             } 
            
            foreach(String item in SelctedItems)
            {
                BchExamsList.Add(new analys
                {
                    name = item
                }) ;
            }

But I'm getting an inavlid cast exception Impossible to cast an object of type 'System.Data.Entity.DynamicProxies.analys_F69488E20B133B223573E1D5931B83214F85574493596933EB8BFDBD5F513C59' in type 'System.Windows.Controls.CheckBox'.' which I try to resolve. But a I failed.

Please I need some help. Thanks.

Answer 1

in this line

foreach ( CheckBox item in _biochimieExam.BiochimieExamsItemsControl.Items )

you are trying to treat every element in _biochimieExam.BiochimieExamsItemsControl.Items as a Checkbox, but elements in _biochimieExam.BiochimieExamsItemsControl.Items ar of type analys .

try this instead:

foreach (analys item in _biochimieExam.BiochimieExamsItemsControl.CheckedItems)
{
    BchExamsList.Add(new analys
    {
        name = item.name
    });
}

Answer 2

I finally resolve the problem by using the CheckListBox of Xceed toolkit package.

My objective was to get the value of checked checkBoxes. In first I was using a ListBox with CheckBoxes as it's items. And that is why I write this code

foreach ( CheckBox item in  _biochimieExam.BiochimieExamsItemsControl.Items )
             {
                 if(item.IsChecked == true)
                 {
                   //  String exam = item.Content.ToString();
                     SelctedItems.Add(item.Content.ToString());
                 }
             } 
            
            foreach(String item in SelctedItems)
            {
                BchExamsList.Add(new analys
                {
                    name = item
                }) ;
            }

To resolve my problem I make these changes in my code:

the Xaml

 <XceedToolkit:CheckListBox Margin="5,5" x:Name="BiochimieExamsItemsControlXceed" 
                                   ValueMemberPath="name"  DisplayMemberPath="name" FontWeight="Bold"
                                   SelectedMemberPath="name" SelectedValue="{Binding SelectedValue}"  
                                   SelectedItemsOverride="{Binding SelectedItems}"
                                   Style="{DynamicResource ListAnalysesItemsControlXceed}" ItemSelectionChanged="BiochimieExamsItemsControlXceed_ItemSelectionChanged" >

            <XceedToolkit:CheckListBox.Resources>
                <Style TargetType="CheckBox">
                    <Style.Triggers>
                        <Trigger Property="IsChecked" Value="True">
                            <Setter Property="Background" Value="white"></Setter>
                        </Trigger>
                        <Trigger Property="IsMouseOver" Value="True">
                            <Setter Property="Background" Value="Gray"></Setter>
                        </Trigger>
                        <Trigger Property="IsKeyboardFocusWithin" Value="True">
                            <Setter Property="Background" Value="white"></Setter>
                        </Trigger>
                    </Style.Triggers>
                    <Setter Property="Background" Value="White" />
                    <Setter Property="MinHeight" Value="16"/>
                    <Setter Property="VerticalContentAlignment" Value="Center"/>
                    <Setter Property="Margin" Value="8,2"/>
                    
                    
                 
              
                </Style>
            </XceedToolkit:CheckListBox.Resources>
            
        </XceedToolkit:CheckListBox>

And in the code behind:

public ObservableCollection<Object> BchSelectedExams { get; set; }


        public void BiochimieExamsItemsControlXceed_ItemSelectionChanged(object sender, Xceed.Wpf.Toolkit.Primitives.ItemSelectionChangedEventArgs e)
        {
           
            BchSelectedExams = (ObservableCollection<object>)BiochimieExamsItemsControlXceed.SelectedItems;
           

            foreach (analys o in BiochimieExamsItemsControlXceed.SelectedItems)
            {
                Console.WriteLine(o.name);
              
            }


        }