C# Web控件与数据感应之 ListControl 类

public void simpleDataList(string DbServerType,string strConn,string sql,ArrayList paras,string keyfield,string displayfield,System.Web.UI.WebControls.ListControl _object,bool allownull,string allownullvalue,string allownulltext)
{
			
			System.Data.IDbConnection Conn=GetConnection(DbServerType,strConn);
			System.Data.IDbCommand Cmd=GetCommand(DbServerType,sql,paras,Conn);

			System.Data.IDataReader myDr=GetDataReader(DbServerType);
			try
			{
				Conn.Open();
                if (DbServerType.ToLower() == "dm8")
                {
                    myDr = Cmd.ExecuteReader() as DmDataReader;
                }
                else
                {
                    myDr = Cmd.ExecuteReader();
                }
				_object.DataSource = myDr;
				_object.DataTextField = displayfield;
				_object.DataValueField = keyfield;
				_object.DataBind();

				myDr.Close();

			}
			catch (SqlException)
			{
			}
			finally
			{
				Conn.Close();
				Conn.Dispose();
			}
			if(allownull)
			{
				_object.Items.Insert (0,new ListItem(allownulltext,allownullvalue));
			}
}//simpleDataList


public System.Data.IDbConnection GetConnection(string DbServerType,string ConnectionString)
{
			IDbConnection con = null;
			switch (DbServerType.ToLower())
			{
				case "oracle":
					con = new OracleConnection(ConnectionString);break;
                case "dm8":
                    con = new DmConnection(ConnectionString); break;
                default:
					con = new SqlConnection(ConnectionString);   break;
			}
			return con;

}
public IDbCommand GetCommand(string dbservertype,string cmdText,ArrayList paras,IDbConnection con)
{
			IDbCommand cmd = null;
			switch (dbservertype.ToLower())
			{
				case "oracle": cmd = new OracleCommand(cmdText,(OracleConnection)con);
					break;
                case "dm8":
                    cmd = new DmCommand(cmdText, (DmConnection)con);
                    break;
                default:    cmd = new SqlCommand(cmdText,(SqlConnection)con);        break;
			}
			if(paras!=null)
			{
				for(int i=0;i<paras.Count;i++)
				{
					cmd.Parameters.Add(GetParameter(dbservertype,paras[i]));
				}
			}
			return cmd;
}
public System.Data.IDbDataParameter GetParameter(string dbservertype,object paras)
{
			IDbDataParameter para = null;
			switch (dbservertype.ToLower())
			{

				case "oracle": para =(OracleParameter)paras; 
					break;
                case "dm8":
                    para =  (DmParameter)paras;
                    break;
                default: para =(SqlParameter)paras; break;
			}
			return para;
}