DAL 要放些什麼? 簡單的說, 就是處理資料的部分.

但是與UI拆開後, 最大的差異, 就是要先將資料處理成UI與DAL可以溝通的

在這裡我們用 DataView, 所以加入 PopulateDataView 將資料轉成DataView

using MySql.Data.MySqlClient;
using System;
using System.Data;

namespace DAL
{
public class GetStockData
{
private static MySqlCommand cmd;
private static MySqlConnection conn;

public static DataView GetDatabases()
{
MySqlDataReader reader = null;

var serverName = "10.10.10.231";
var uidName = "root";
var pwdName = "80324831";
var databaseName = "BDS";
string connStr = String.Format("server={0};uid={1};pwd={2};database={3}",
serverName, uidName, pwdName, databaseName);

try
{

conn = new MySqlConnection(connStr);
conn.Open();

MySqlCommand cmd = new MySqlCommand("SELECT * FROM STOCKSCODE", conn);

reader = cmd.ExecuteReader();

DataView myDataView = PopulateDataView(reader, "myTable");
return myDataView;
//while (reader.Read())
//{
// listBox2.Items.Add(reader.GetString(0));
//}
}
catch (MySqlException ex)
{
return null;
// MessageBox.Show("Failed to populate database list: " + ex.Message);
}
finally
{
if (reader != null) reader.Close();
}
}

private static DataView PopulateDataView(IDataReader dataReader, string tableName)
{
DataTable dataReaderTable = new DataTable(tableName);

try
{
for (int count = 0; count < dataReader.FieldCount; count++)
{
DataColumn tempCol = new DataColumn(dataReader.GetName(count), dataReader.GetFieldType(count));

dataReaderTable.Columns.Add(tempCol);
}

while (dataReader.Read())
{
DataRow dr = dataReaderTable.NewRow();

for (int i = 0; i < dataReader.FieldCount; i++)
{
dr[i] = dataReader.GetValue(dataReader.GetOrdinal(dataReader.GetName(i)));
}

dataReaderTable.Rows.Add(dr);
}

return dataReaderTable.DefaultView;
}
catch
{
return null;
}
}
}
}