C＃更新查詢

Question

我發現一個或所需的參數C＃更新查詢沒有給出錯誤的地方我試圖更新我的C＃訪問數據庫這裏是代碼... 希望有人會是我的助手..

private void updatebutton_Click(object sender, EventArgs e) 
{ 
    try 
    { 
     con.Open(); 
     OleDbCommand cmd = new OleDbCommand(); 
     cmd.Connection = con; 
      string query = "update Emplyeedata set [ID]='" + midbox.Text + "',[Name]='" + mnamebox.Text + "',[Deisgnation]='" + mdesbox.Text + "',[Leave]='" + mleavebox.Text + "'Where [Name]='"+mnamebox.Text+"'"; 
     cmd.CommandText = query; 

     cmd.ExecuteNonQuery(); 
     con.Close(); 
     cb(); 
     MessageBox.Show("Updated", "Message", MessageBoxButtons.OK, MessageBoxIcon.Information); 
    } 
    catch 
    { 
     MessageBox.Show("Error", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); 
    }       
} 

Answer 1

作爲一個更多的改進，你可以嘗試這樣，如果你可以發佈完整的錯誤信息。

private void updatebutton_Click() 
    { 
     using (OleDbConnection con = new OleDbConnection("Define your Connection String here")) 
     { 
      string query = @"UPDATE Emplyeedata 
         SET [id] = @ID 
          ,[Name] = @Name 
          ,[Deisgnation] = @Deisgnation 
          ,[Leave] = @Leave 
         WHERE [Name] = @Name"; 

      using (OleDbCommand cmd = new OleDbCommand(query, con) { CommandType = CommandType.Text }) 
      { 
       cmd.Parameters.AddWithValue("@ID", midbox.Text); 
       cmd.Parameters.AddWithValue("@Name", mnamebox.Text); 
       cmd.Parameters.AddWithValue("@Deisgnation", mdesbox.Text); 
       cmd.Parameters.AddWithValue("@Leave", mleavebox.Text); 
       cmd.Parameters.AddWithValue("@Name", mnamebox.Text); 
       con.Open(); 
       cmd.ExecuteNonQuery(); 
      } 
      con.Close(); 
     } 
    } 

（這是一個非常非結構化的方式，請按照SOLID原理/秒）