DD Class9

DataReader

• DataReader http://iam.colum.edu/dd/classsource/ado/dataReader.aspx source

1 Connection Object <csharp> //Connection string comes from web config SqlConnection objConnection = new SqlConnection(ConfigurationManager.ConnectionStrings["cheeseConnectionString"].ConnectionString); </csharp>

web.config connection strings

<xml> <configuration>

              <connectionStrings>

<add name="cheeseConnectionString" connectionString="Data Source=iamdb;Initial Catalog=cheese;User ID=student;Password=Student" providerName="System.Data.SqlClient"/> </connectionStrings> </xml>

2 Command Object <csharp>string strSQL = "SELECT CheeseName,CheeseDescription FROM cheese";

   string strResultsHolder = "";
   
   SqlCommand objCommand = new SqlCommand(strSQL, objConnection);

</csharp>

3 Reader and Reading <csharp> SqlDataReader objDataReader = null; //Reader to read through the result

   try
   {
       objConnection.Open();                                       //Open Connection
       objDataReader = objCommand.ExecuteReader();

       while (objDataReader.Read() == true)
       {
           strResultsHolder += String.Format("{0}:{1}

",
               objDataReader["CheeseName"], objDataReader["CheeseDescription"]);
       }
   }
   catch (Exception e)
   {
       lblErr.Text = "Connection failed to open successfully.
";
       lblErr.Text += e.ToString();
   }
   finally
   {
       objDataReader.Close();      //Close Reader
       objConnection.Close();      //Close Connection

   }
   //Write results
   divListCheese.InnerHtml = strResultsHolder;

}

</csharp>

Review First Normal Form

Let build the example for the homework.

Build Interface to GameDB

Games

GameTitle	GameGenre	DeveloperName	Platform(s)	Year	DeveloperWebsite	GameWebsite
Quake1	FPS	id	Dos	1996	http://www.idsoftware.com/	http://www.idsoftware.com/games/quake/quake/
Diablo	RPG	Blizzard	Windows 95	1996	http://www.blizzard.com/	http://www.blizzard.com/diablo/
SimCity	Sim	Interplay	Dos	1993	http://www.interplay.com/	http://www.maxis.com/

Tables Games, Developers, Websites, Platforms?

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