Question

以下是我在Windows窗体应用程序中的代码的一部分，如何将其转换为WPF，考虑到this.Controls不可用：

public Form1()
        {
            InitializeComponent();
            foreach (TextBox tb in this.Controls.OfType<TextBox>())
            {
                tb.Enter += textBox_Enter;
            }
        }

        void textBox_Enter(object sender, EventArgs e)
        {
            focusedTextbox = (TextBox)sender;
        }

private TextBox focusedTextbox = null;

private void button1_Click (object sender, EventArgs e)
        {
            if (focusedTextbox != null)
            {
                focusedTextbox.Text += "1";

            }
        }

Answer 1

在你的根元素（很可能是Window本身）上收听PreviewGotKeyboardFocus并记录e.NewFocus参数。预览事件会冒泡出可视树，因此任何在父控件中公开一个控件的控件都会触发它（请参阅routed events）。

事件处理程序变为：

    private void OnGotFocusHandler(object sender, KeyboardFocusChangedEventArgs e)
    {
        var possiblyFocusedTextbox = e.NewFocus as TextBox;
        //since we are now receiving all focus changes, the possible textbox could be null
        if (possiblyFocusedTextbox != null)
            focusedTextbox = possiblyFocusedTextbox;
    }

将Windows窗体转换为WPF

1 个答案: