EventHandler 自訂事件

UserControl1.cs

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

public partial class UserControl1 : UserControl { /// <summary> /// 建立事件處理 /// </summary> new public event EventHandler TextChanged; /// <summary> /// 事件處理函數 /// </summary> protected void OnTextChanged() { // 如果有建立事件監聽，則Invoke TextChanged?.Invoke(this.textBox1, new EventArgs()); } public UserControl1() { InitializeComponent(); } /// <summary> /// 使用者控制項 的 TextBox 預設 TextChanged 事件 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void textBox1_TextChanged(object sender, EventArgs e) { OnTextChanged(); } }

Form1.cs

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { // 針對使用者控制項新增自訂的 TextChanged 事件 this.userControl11.TextChanged += UserControl11_TextChanged; } /// <summary> /// 使用者控制項新增自訂的 TextChanged 事件處理函數 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void UserControl11_TextChanged(object sender, EventArgs e) { if (sender is TextBox) { TextBox tb = sender as TextBox; label1.Text = tb.Text; } } }