MessageBox Fehler System.EventArgs enthält keine Definition

Question

Ich versuche, eine MessageBoxButtons.YesNo zu machen, und ich weiß, dass Sie einen Dialog für formclosing machen können, aber ich wollte dies für eine meiner EXIT-Tasten machen. Ich erhalte diesen Fehler, wo ich e.Canel = true in Button3 erklärt

Hier ist mein Code:

using LOGINPAGE.Models; 
using System; 
using System.Collections.Generic; 
using System.ComponentModel; 
using System.Data; 
using System.Drawing; 
using System.Linq; 
using System.Text; 
using System.Threading.Tasks; 
using System.Windows.Forms; 

namespace LOGINPAGE 
{ 
    public partial class FACULTY : Form 
    { 
     public FACULTY() 
     { 
      InitializeComponent(); 

      SetFloorsToDropDown(); 
     } 

     private void FACULTY_Load(object sender, EventArgs e) 
     { 
      // TODO: This line of code loads data into the 'roomInfoDataSet2.Table' table. You can move, or remove it, as needed. 
      this.tableTableAdapter1.Fill(this.roomInfoDataSet2.Table); 
      // TODO: This line of code loads data into the 'roomInfoDataSet1.Table' table. You can move, or remove it, as needed. 
      this.tableTableAdapter.Fill(this.roomInfoDataSet1.Table); 


     } 

     private void xButton5_Click(object sender, EventArgs e) 
     { 

      Floor.SelectedIndex = -1; 
     } 

     private void xButton2_Click(object sender, EventArgs e) 
     { 

      this.Close(); 
      Application.Exit(); 
     } 

     private void xButton3_Click(object sender, EventArgs e) 
     { 
      DialogResult dialog = MessageBox.Show("Do you want to Exit?", "Exit", MessageBoxButtons.YesNo, MessageBoxIcon.Warning); 
      if (dialog == DialogResult.Yes) 
      { 
       Application.Exit(); 
      } 
      else 
      { 

       e.Cancel = true; 
      } 

     } 

     private void checkBox1_CheckedChanged(object sender, EventArgs e) 
     { 

     } 

     private void xButton1_Click(object sender, EventArgs e) 
     { 

     } 

     private void Floor_SelectedIndexChanged(object sender, EventArgs e) 
     { 
      dataGridView1.Rows.Clear(); 

      if (Floor.SelectedItem.ToString() != "SELECT FLOOR") 
      { 
       foreach (var item in roomInfoDataSet1.Table.Where(x => x.Room_Number.Substring(0, 1) == Convert.ToString(Floor.SelectedValue))) 
       { 
        string[] row = new string[] { item.Room_Number, Convert.ToString(Floor.SelectedValue) }; 

        dataGridView1.Rows.Add(row); 
        dataGridView1.ClearSelection(); 
        dataGridView1.Rows[dataGridView1.Rows.Count - 1].Selected = true; 
        dataGridView1.FirstDisplayedScrollingRowIndex = dataGridView1.Rows.Count - 1; 
       } 
      } 
     } 

     private void SetFloorsToDropDown() 
     { 
      List<DropDownModel> floorList = new List<DropDownModel>(); 

      floorList.Add(new DropDownModel() 
      { 
       Id = 0, 
       Name = "SELECT FLOOR", 
      }); 

      floorList.Add(new DropDownModel() 
      { 
       Id = 1, 
       Name = "1st Floor", 
      }); 

      floorList.Add(new DropDownModel() 
      { 
       Id = 2, 
       Name = "2nd Floor", 
      }); 

      floorList.Add(new DropDownModel() 
      { 
       Id = 3, 
       Name = "3rd Floor", 
      }); 

      floorList.Add(new DropDownModel() 
      { 
       Id = 4, 
       Name = "4th Floor", 
      }); 

      floorList.Add(new DropDownModel() 
      { 
       Id = 5, 
       Name = "5th Floor", 
      }); 

      floorList.Add(new DropDownModel() 
      { 
       Id = 6, 
       Name = "6th Floor", 
      }); 

      Floor.DataSource = floorList; 
      Floor.DisplayMember = "Name"; 
      Floor.ValueMember = "Id"; 
     } 



     private void dataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e) 
     { 

     } 

     private void xButton1_Click_1(object sender, EventArgs e) 
     { 

     } 



    } 
} 

Answer 1

So, wie ich das Problem verstanden in xButton3_Click() ist. Ändern Sie ihn auf:

private void xButton3_Click(object sender, EventArgs e) 
{ 
    DialogResult dialog = MessageBox.Show("Do you want to Exit?", "Exit", MessageBoxButtons.YesNo, MessageBoxIcon.Warning); 
    if (dialog == DialogResult.Yes) 
    { 
     Application.Exit(); 
    } 
} 

Sie brauchen nicht else zu verwenden. Lass es einfach so wie es ist. Wenn der Benutzer "Ja" wählt, wird die Anwendung geschlossen, auf andere Weise sind keine Maßnahmen erforderlich.