c# code for select all checkbox in wpf datagrid

Question

I need some c# code to select / deselect all checkboxes in a datagrid in WPF 3.5 framework. I would like to do this by clicking a single header checkbox in the grid.

Answer 1

This is based on someone else's source that I can't recall, but we use it to help find visual children of a type. It may not be the most efficient use for this scenario but it might help get you on the right track.

    public static childItem FindVisualChild(DependencyObject obj) where childItem : DependencyObject
    {
        for (int i = 0; i < VisualTreeHelper.GetChildrenCount(obj); i++)
        {
            DependencyObject child = VisualTreeHelper.GetChild(obj, i);
            if (child != null && child is childItem)
                return (childItem)child;

            childItem childOfChild = FindVisualChild(child);
            if (childOfChild != null)
                return childOfChild;
        }
        return null;
    }

[Edit 4.16.09] Based on that, try out this method. Should find all CheckBoxes and change the state as provided, callable from your event handler on the Checked/Unchecked events.

   public static void CheckAllBoxes(DependencyObject obj, bool isChecked)
    {
        for (int i = 0; i < VisualTreeHelper.GetChildrenCount(obj); i++)
        {
            // If a checkbox, change IsChecked and continue.
            if (obj is CheckBox)
            {
                ((CheckBox) obj).IsChecked = isChecked;
                continue;
            }

            DependencyObject child = VisualTreeHelper.GetChild(obj, i);
            CheckAllBoxes(child, isChecked);
        }
    }