Get WPF window by hWnd

Window window = (Window)HwndSource.FromHwnd(hWnd).RootVisual

As far as I know WPF completely replaces WinApi model with all that HWNDs. Main window has HWND of course, because it servers as container between WinApi and WPF. You can access HWND using WindowInteropHelper Class, like this. But you will not be able to traverse controls the same way you would do it with native or WinForms app. Check VisualTreeHelper for traversing control trees in WPF.

After you get the window itself (as Marat points out how to do that) you need to search the visual tree. Here are two helper functions

find all children of a type

public static IEnumerable<T> FindChildren<T>(this DependencyObject source) where T : DependencyObject    {      if (source != null)      {        var childs = GetChildObjects(source);        foreach (DependencyObject child in childs)        {          //analyze if children match the requested type          if (child != null && child is T)          {            yield return (T)child;          }          //recurse tree          foreach (T descendant in FindChildren<T>(child))          {            yield return descendant;          }        }      }    }

https://sites.google.com/site/bobstechwiki/home/wpf-ji-shu-1/find-element-by-visual-tree

to find a child by name:

 public static T FindChild<T>(DependencyObject parent, string childName)       where T : DependencyObject    {          // Confirm parent and childName are valid.       if (parent == null) return null;      T foundChild = null;      int childrenCount = VisualTreeHelper.GetChildrenCount(parent);      for (int i = 0; i < childrenCount; i++)      {        var child = VisualTreeHelper.GetChild(parent, i);        // If the child is not of the request child type child        T childType = child as T;        if (childType == null)        {          // recursively drill down the tree          foundChild = FindChild<T>(child, childName);          // If the child is found, break so we do not overwrite the found child.           if (foundChild != null) break;        }        else if (!string.IsNullOrEmpty(childName))        {          var frameworkElement = child as FrameworkElement;          // If the child's name is set for search          if (frameworkElement != null && frameworkElement.Name == childName)          {            // if the child's name is of the request name            foundChild = (T)child;            break;          }        }        else        {          // child element found.          foundChild = (T)child;          break;        }      }      return foundChild;    }

How can I find WPF controls by name or type?