爲什麼我得到這個問題「附加信息：無法找到對象」設備「，因爲它不存在。」

Question

我嘗試編寫設備管理工具，但我無法將新信息保存到數據庫。我的部分代碼如下。非常感謝。

private void button1_Click(object sender, EventArgs e) 
{ 
     if (checkValidDate() == 1) 
     { 

      if (MessageBox.Show("Location: " + comboBox1Selected + Environment.NewLine + 
           "Device Type: " + comboBox2Selected + Environment.NewLine + 
           "Device ID: " + textBox1.Text + Environment.NewLine + 
           "Serial Number: " + textBox2.Text + Environment.NewLine + 
           "Warranty Exp Date: " + textBox3.Text + Environment.NewLine + 
           "Memo: " + textBox4.Text + Environment.NewLine + 
           "UserName: " + textBox5.Text + Environment.NewLine + 
           "Room Num: " + textBox6.Text, "Confirm", MessageBoxButtons.OKCancel, MessageBoxIcon.Question) == DialogResult.OK) 
      { 
       // user clicked yes 
       MessageBox.Show("3333333333"); 
       addToDataBase(); 
      } 
      else 
      { 
       // user clicked no 
      } 
     } 
     else 
     { 

     } 
    } 

private void button2_Click(object sender, EventArgs e) 
{ 
    if (MessageBox.Show("Are you sure?", "Confirm", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes) 
    { 
     // user clicked yes 
    } 
    else 
    { 
     // user clicked no 
    } 
} 

Answer 1

if (checkValidDate() == 1) 
{ 
    DialogResult result = MessageBox.Show("Do you want to save changes?", "Confirmation", MessageBoxButtons.YesNoCancel); 
    if(result == DialogResult.Yes) 
    { 
     //...write your code here that will save data to the database 
    } 
    else if (result == DialogResult.No) 
    { 
     //... 
    } 
    else 
    { 
     //... 
    } 
}