OleDbConnection連接錯誤

Question

我寫了這些代碼塊：

ConnectDB.getConStr（）;

  string query = "insert into users (memberName,memberSurname,memberEmail,userName,userPassword) values(@mn,@msn,@me,@un,@up)"; 
     OleDbCommand cmd = new OleDbCommand(query,ConnectDB.getConStr()); 
     cmd.Parameters.AddWithValue("@mn", txtName.Text); 
     cmd.Parameters.AddWithValue("@msn", txtSurname.Text); 
     cmd.Parameters.AddWithValue("@me", txtEmail.Text); 
     cmd.Parameters.AddWithValue("@un", txtUsername.Text); 
     cmd.Parameters.AddWithValue("@up", txtPassword.Text); 

     try 
     { 
      ConnectDB.getConStr().Open(); 
      cmd.ExecuteNonQuery(); 
      ConnectDB.getConStr().Close(); 
      ltrMesaj.Text = "Record has been added"; 
      Response.Redirect("Login.aspx"); 
     } 
     catch (Exception ex) 
     { 
      ltrMesaj.Text = ex.Message; 
     } 

但是我得到了這樣的錯誤：ExecuteNonQuery需要一個開放的可用Connection。連接的當前狀態已關閉。

我該如何解決這個問題？

Answer 1

您正在創建新的instances的connection每次訪問它時。所以只能創建一個instance和使用它像這樣

OleDbConnection connection= ConnectDB.getConStr(); 
    string query = "insert into users (memberName,memberSurname,memberEmail,userName,userPassword) values(@mn,@msn,@me,@un,@up)"; 
     OleDbCommand cmd = new OleDbCommand(query,connection); 
     cmd.Parameters.AddWithValue("@mn", txtName.Text); 
     cmd.Parameters.AddWithValue("@msn", txtSurname.Text); 
     cmd.Parameters.AddWithValue("@me", txtEmail.Text); 
     cmd.Parameters.AddWithValue("@un", txtUsername.Text); 
     cmd.Parameters.AddWithValue("@up", txtPassword.Text); 

     try 
     { 
      connection.Open(); 
      cmd.ExecuteNonQuery(); 
      connection.Close(); 
      ltrMesaj.Text = "Record has been added"; 
      Response.Redirect("Login.aspx"); 
     } 
     catch (Exception ex) 
     { 
      ltrMesaj.Text = ex.Message; 
     }