C＃Form X Button Clicked

Question

如何通過單擊X按鈕或（this.Close（））找出表單是否關閉？

Answer 1

表單具有帶FormClosing類型的參數的事件FormClosingEventArgs。

private void Form1_FormClosing(object sender, FormClosingEventArgs e) 
{ 
    if (e.CloseReason == CloseReason.UserClosing) 
    { 
     if (MessageBox.Show(this, "Really?", "Closing...", 
      MessageBoxButtons.OKCancel, MessageBoxIcon.Question) 
      == DialogResult.Cancel) e.Cancel = true; 
    } 
} 

Answer 2

你可以一起刪除'X'嗎？

一種形式的屬性是如果你想設置的返回字段設置爲null，像你一樣，當你點擊你的表格取消「控制盒」只是將其設置爲false

Answer 3

：

private void Form1_FormClosing(object sender, FormClosingEventArgs e) 
{ 
    if (e.CloseReason == CloseReason.UserClosing) 
    { 
     returnfield = null; 
     this.close(); 
    } 
} 

Answer 4

對於OnFormClosing的FormClosingEventArgs.CloseReason是UserClosing要麼「X」按鈕或form.Close()方法。 我的解決方案：

//override the OnFormClosing event 
     protected override void OnFormClosing(FormClosingEventArgs e) 
     { 
      if (e.CloseReason == CloseReason.ApplicationExitCall)// the reason that you need 
       base.OnFormClosing(e); 
      else e.Cancel = true; // cancel if the close reason is not the expected one 
     } 
//create a new method that allows to handle the close reasons 
     public void closeForm(FormClosingEventArgs e) 
     { 
      if (e.CloseReason == CloseReason.UserClosing) this.Close(); 
      else e.Cancel = true; 
     } 

    //if you want to close the form or deny the X button action invoke closeForm method 
    myForm.closeForm(new FormClosingEventArgs(CloseReason.ApplicationExitCall, false)); 
           //the reason that you want ↑ 

在這個例子中的關閉（X）按鈕不關閉窗體