C# 通过脚本确定WPF中哪个控件具有焦点

如何确定哪个控件在C#中具有焦点

例如：

private void button_Click(object sender, RoutedEventArgs e)
{
    Update(Brushes.White, textBox);   /*Here there my textBox has focus.*/

    //... (some codes)

    NotCorrect();

    //... (some codes)
}

private void NotCorrect()
{
    Update(textblock.background, /*I mean here : the focus remains where it is already, on the textBox.*/);
    textBlock.text = "Try again..."
}

private void Update(Brushes myBrush, Control myControl)
{
    texBlock.Background = myBrush;
    myControl.Focus();
}

在NotCorrect（）方法中：

背景意味着：我想要与已经存在的笔刷相同的笔刷（参见点击事件的第一行），我不想改变任何东西

（我更喜欢写textBlock.Background而不是重写笔刷.White。）

---

现在我问是否还有一种方式可以说：我希望焦点保持在它已经存在的控件上，我不想更改任何内容。

Form.ActiveControl是您应该搜索的

• 我发现了一种使用null的解决方案：

  private void button_Click(object sender, RoutedEventArgs e)
  {
      Update(Brushes.White, textBox);
  
      //... (some codes)
  
      NotCorrect();
  
      //... (some codes)
  }
  
  private void NotCorrect()
  {
      Update(textblock.background, null);
      textBlock.text = "Try again..."
  }
  
  private void Update(Brushes myBrush, Control myControl)
  {
      texBlock.Background = myBrush;
      if (myControl != null)
          myControl.Focus();
  }
  

  private void button_Click(object sender, RoutedEventArgs e)
  {
      Update(Brushes.White, textBox);
  
      //... (some codes)
  
      NotCorrect();
  
      //... (some codes)
  }
  
  private void NotCorrect()
  {
      Update(textblock.background, this);
      textBlock.text = "Try again..."
  }
  
  private void Update(Brushes myBrush, Control myControl)
  {
      texBlock.Background = myBrush;
      myControl.Focus();
  }
  

• 我发现的另一个更简单的解决方案是使用

  这个

  ：

  private void button_Click(object sender, RoutedEventArgs e)
  {
      Update(Brushes.White, textBox);
  
      //... (some codes)
  
      NotCorrect();
  
      //... (some codes)
  }
  
  private void NotCorrect()
  {
      Update(textblock.background, null);
      textBlock.text = "Try again..."
  }
  
  private void Update(Brushes myBrush, Control myControl)
  {
      texBlock.Background = myBrush;
      if (myControl != null)
          myControl.Focus();
  }
  

  private void button_Click(object sender, RoutedEventArgs e)
  {
      Update(Brushes.White, textBox);
  
      //... (some codes)
  
      NotCorrect();
  
      //... (some codes)
  }
  
  private void NotCorrect()
  {
      Update(textblock.background, this);
      textBlock.text = "Try again..."
  }
  
  private void Update(Brushes myBrush, Control myControl)
  {
      texBlock.Background = myBrush;
      myControl.Focus();
  }
  

---

谢谢您的回答，但它似乎不起作用。如果你写一行正确的代码，我会理解得更好。