从Access数据库获取数据的正确方法

Question

我对如何从访问数据库获取数据感到困惑.在List中首先收集它然后从列表中获取这些数据是否合适？或者可以直接在数据库中获取它？

我的代码工作得很好,但我想知道是否有更好的方法来做到这一点？:

 private void button3_Click(object sender, EventArgs e)
    {
        OleDbConnection connection = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\redgabanan\Desktop\Gabanan_Red_dbaseCon\Red_Database.accdb");
        connection.Open();
        OleDbDataReader reader = null;
        OleDbCommand command = new OleDbCommand("SELECT * from  Users WHERE LastName='"+textBox8.Text+"'", connection);
        reader = command.ExecuteReader();
        listBox1.Items.Clear();

        while (reader.Read())
        {

            listBox1.Items.Add(reader[1].ToString()+","+reader[2].ToString());
        }

        connection.Close();

*我直接从数据库中获取记录,然后将其显示在列表框中.

Answer 1

像拇指一样伸出的一件事是SQLInjection并使用Parameterised查询,例如:

OleDbCommand command = new OleDbCommand("SELECT * from  Users WHERE LastName='@1'", connection);

command.Parameters.AddWithValue("@1", textBox8.Text)

你做的事情是完全可以接受的,尽管你通常最好使用SQL数据库.

编辑:以下是如何从GUI分离业务逻辑:

Class BusLogic
{
 public List<string> ListboxItems = new List<string>();
 public void PopulateListBoxItems(string userName)
 {
  string connString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\redgabanan\Desktop\Gabanan_Red_dbaseCon\Red_Database.accdb";
  using (OleDbConnection connection = new OleDbConnection(connString))
  {
        connection.Open();
        OleDbDataReader reader = null;
        OleDbCommand command = new OleDbCommand("SELECT * from  Users WHERE LastName='@1'", connection);            
        command.Parameters.AddWithValue("@1", userName)
        reader = command.ExecuteReader();    
        while (reader.Read())
        {
            ListboxItems.Add(reader[1].ToString()+","+reader[2].ToString());
        }    
   }
 }    
}

GUI

private void button3_Click(object sender, EventArgs e)
{        
      var busLogic = new BusLogic();
      busLogic.PopulateListBoxItems(textBox8.Text);          
      \\listBox1.Items.Clear();
      ListboxItems.DataSource = busLogic.ListboxItems;
}