Looping over XAML defined labels

Question

I have a WPF application with many labels.

....
         


        

Answer 1

You could add all those Label to a List<Label> within the form's constructor.

It is a tedious work, but you'll only have to do it once.

List<Label> labels = new List<Label>();
labels.Add(label1);
// etc.

// loop
for (int i = 0; i < labels.Count; i++)
    labels[i].Text = i.ToString();

// alternative loop
foreach (Label label in labels)
    label.Text = "test";

Answer 2

You can make it with binding !

xaml view:

<ItemsControl ItemsSource="{Binding List}">
    <ItemsControl.ItemTemplate>
        <DataTemplate>
            <Label Content="{Binding Value, Mode=TwoWay}"/>
        </DataTemplate>
    </ItemsControl.ItemTemplate>
</ItemsControl>

in code behind in the constructor:

DataContext = new ViewModelClass();

in ViewModelClass:

class ViewModelClass : INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;

        private void NotifyPropertyChanged(string name)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
        }

        private ObservableCollection<StringObject> _List = new ObservableCollection<StringObject>();
        public ObservableCollection<StringObject> List
        {
            get { return _List; }
            set
            {
                _List = value;
                NotifyPropertyChanged("List");
            }
        }

        public ViewModelClass()
        {
            List = new ObservableCollection<StringObject>
                {
                    new StringObject {Value = "your"},
                    new StringObject {Value = "list"},
                    new StringObject {Value = "of"},
                    new StringObject {Value = "string"}
                };
        }
    }

    public class StringObject
    {
        public string Value { get; set; }
    }

Be careful with a collection with type string it doesn't work, you have to use an object => StringObject

Answer 3

How about this?

List<Label> labelL = new List<Label>();

for(int i = 1; i<40 ;i++)
    labelL.Add(new Label{ Name = "label"+i, Content = i*10 });

The end result will be this.

label1.Text = 10;
label2.Text = 20;
label3.Text = 20;
...
...

Answer 4

If your labels are all named consistently, you can do it like this:

var numberOfLabels = 40;

for(int i = 1; i <= numberOfLabels; i++)
{
    var labelName = string.Format("label{0}", i);
    var label = (Label) this.FindName(labelName);
    label.Content = i * 10;
}

Answer 5

Using this code

public static IEnumerable<T> FindVisualChildren<T>(DependencyObject depObj) where T : DependencyObject
{
    if (depObj != null)
    {
        for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
        {
            DependencyObject child = VisualTreeHelper.GetChild(depObj, i);
            if (child != null && child is T)
            {
                yield return (T)child;
            }

            foreach (T childOfChild in FindVisualChildren<T>(child))
            {
                yield return childOfChild;
            }
        }
    }
}

You can enumerate all controls by type.

foreach (Label lbl in FindVisualChildren<Label>(window))
{
    // do something with lbl here
}

Answer 6

If you work with binding it is easy. You just have to keep your label content in an ObservableCollection<string> on your ViewModel. And then, you can do whatever you want with them, in your case iteration.

Edit 1:

Also your xaml should be something like:

        <ItemsControl ItemsSource="{Binding MyLabelValues}">
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <sdk:Label Content="{Binding Mode=TwoWay}"></sdk:Label>
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>