Difference between revisions of "DD Class9"

esse quam videri
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m (Text replacement - "syntaxhighlight lang="csharp" line="1" " to "syntaxhighlight lang="csharp"")
 
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First we can start with the cheese definition
 
First we can start with the cheese definition
  
<csharp>
+
<syntaxhighlight lang="csharp">
 
  public class Cheese
 
  public class Cheese
 
     {
 
     {
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         public string CheeseDescription { get; set; }
 
         public string CheeseDescription { get; set; }
 
     }
 
     }
</csharp>
+
</syntaxhighlight>
 
Then interface for the repo
 
Then interface for the repo
<csharp>
+
<syntaxhighlight lang="csharp">
 
public interface IRepository<T>
 
public interface IRepository<T>
 
     {
 
     {
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         void Remove(T entity);
 
         void Remove(T entity);
 
     }
 
     }
</csharp>
+
</syntaxhighlight>
 
Now we want to expand the interface definition to cheeses
 
Now we want to expand the interface definition to cheeses
<csharp>
+
<syntaxhighlight lang="csharp">
 
/// <summary>
 
/// <summary>
 
     /// ICheeseRepo Changes the type of the Generic Repo To Cheese
 
     /// ICheeseRepo Changes the type of the Generic Repo To Cheese
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         //Cheese GetByName(string name)
 
         //Cheese GetByName(string name)
 
     }
 
     }
</csharp>
+
</syntaxhighlight>
 
Finally the repo interface can then be implemented like this
 
Finally the repo interface can then be implemented like this
<csharp>
+
<syntaxhighlight lang="csharp">
 
public class TestCheeseRepository : ICheeseRepo
 
public class TestCheeseRepository : ICheeseRepo
 
     {
 
     {
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         }
 
         }
 
     }
 
     }
</csharp>
+
</syntaxhighlight>
  
 
Link to the implememtation http://iam.colum.edu/datadesign/gbrowser.php?file=/App_code/Repo/CheeseRepo.cs
 
Link to the implememtation http://iam.colum.edu/datadesign/gbrowser.php?file=/App_code/Repo/CheeseRepo.cs
Line 110: Line 110:
 
http://iam.colum.edu/datadesign/gbrowser.php?file=/classsource/repo/Default.aspx.cs
 
http://iam.colum.edu/datadesign/gbrowser.php?file=/classsource/repo/Default.aspx.cs
  
<csharp>
+
<syntaxhighlight lang="csharp">
 
ICheeseRepo db = new TestCheeseRepository();
 
ICheeseRepo db = new TestCheeseRepository();
 
         gv1.DataSource = db.GetCheeses();
 
         gv1.DataSource = db.GetCheeses();
 
         gv1.DataBind();
 
         gv1.DataBind();
</csharp>
+
</syntaxhighlight>
  
  
  
 
You can add LINQ helpers to the class
 
You can add LINQ helpers to the class
<csharp>
+
<syntaxhighlight lang="csharp">
 
/// <summary>
 
/// <summary>
 
     /// Cheese Class for Our Repo
 
     /// Cheese Class for Our Repo
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         public string CheeseDescription { get; set; }
 
         public string CheeseDescription { get; set; }
 
     }
 
     }
</csharp>
+
</syntaxhighlight>
  
 
and then create a new cheese repo
 
and then create a new cheese repo
Line 139: Line 139:
 
and update your repo initialization
 
and update your repo initialization
  
<csharp>
+
<syntaxhighlight lang="csharp">
 
ICheeseRepo db = new CheeseRepository(ConfigurationManager.ConnectionStrings["cheeseConnectionString"].ToString());  
 
ICheeseRepo db = new CheeseRepository(ConfigurationManager.ConnectionStrings["cheeseConnectionString"].ToString());  
 
         gv1.DataSource = db.GetCheeses();
 
         gv1.DataSource = db.GetCheeses();
 
         gv1.DataBind();
 
         gv1.DataBind();
</csharp>
+
</syntaxhighlight>
 
 
 
 
 
 
  
 +
LINQ classes in MVC must use the entire namespace
 +
<syntaxhighlight lang="csharp">
 +
/// <summary>
 +
    /// Cheese Class for Our Repo
 +
    /// </summary>
 +
    [System.Data.Linq.Mapping.Table(Name = "Cheese")]
 +
    public class Cheese
 +
    {
 +
        [System.Data.Linq.Mapping.Column(IsPrimaryKey = true, IsDbGenerated = true, AutoSync = AutoSync.OnInsert)]
 +
        public int CheeseID { get; set; }
 +
        [System.Data.Linq.Mapping.Column]
 +
        public string CheeseName { get; set; }
 +
        [System.Data.Linq.Mapping.Column]
 +
        public string CheeseDescription { get; set; }
 +
    }
 +
</syntaxhighlight>
  
 
==Homework==
 
==Homework==
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Use the repo pattern to create a repo for you own class. The the class should map to a table in your database. The repo should be able to show items in you db, add items and remove items.  
 
Use the repo pattern to create a repo for you own class. The the class should map to a table in your database. The repo should be able to show items in you db, add items and remove items.  
  
I'll give 1 pt extra for updating items.
+
Add the repo to your Web from site and your MVC site. The repose should be able to list items from the DB. Either the MVC site or the WebForms site should be able to add and delete items.
 +
I'll give 1 pt extra for updating items and 1 pt for adding/deleting in MVC and Web Forms.

Latest revision as of 03:20, 9 February 2016


Repo Pattern

Definition from P of EE http://martinfowler.com/eaaCatalog/repository.html MSDN The Repository Pattern

The repository pattern is a nice way to abstract data fetching logic and easily separate concerns from different layers of your app. It allows of to quickly refactor and swap repos.

First we can start with the cheese definition

 public class Cheese
    {
        
        public int CheeseID { get; set; }
        
        public string CheeseName { get; set; }
        
        public string CheeseDescription { get; set; }
    }

Then interface for the repo

public interface IRepository<T>
    {
        T GetById(int id);
        List<T> GetItems();
        void Add(T entity);
        void Remove(T entity);
    }

Now we want to expand the interface definition to cheeses

/// <summary>
    /// ICheeseRepo Changes the type of the Generic Repo To Cheese
    /// </summary>
    public interface ICheeseRepo : IRepository<Cheese>
    {
        List<Cheese> GetItems();
        List<Cheese> GetCheeses();  //New Method To Get Cheeses
        //May want to expand the definition to get cheese by name
        //Cheese GetByName(string name)
    }

Finally the repo interface can then be implemented like this

public class TestCheeseRepository : ICheeseRepo
    {

        //could grab these from the Application Object
        private static List<Cheese> fakeCheeses =
            new List<Cheese> { new Cheese { CheeseID=1, CheeseName="test1", CheeseDescription = "test desc 1" },
                new Cheese { CheeseID=2, CheeseName="test2", CheeseDescription = "test desc 2" },
                new Cheese { CheeseID=2, CheeseName="test3", CheeseDescription = "test desc 3" }
            };


        #region ICheeseRepo Members
        public List<Cheese> GetItems()
        {
            return GetCheeses();
        }


        public List<Cheese> GetCheeses()
        {
            return fakeCheeses.ToList();
        }

        #endregion

        #region IRepository<Cheese> Members

        public Cheese GetById(int id)
        {
            //linq statement to find cheese by ID
            var currentCheese = from c in fakeCheeses where c.CheeseID == id select c;
            return currentCheese.FirstOrDefault();
        }

        public void Add(Cheese entity)
        {
            fakeCheeses.Add(entity);
        }

        public void Remove(Cheese entity)
        {
            fakeCheeses.Remove(entity);
        }

        #endregion

        //added statement to find cheese by name
        public Cheese GetByName(string name)
        {
            //linq statement to find cheese by name
            var currentCheese = from c in fakeCheeses where c.CheeseName == name select c;
            return currentCheese.FirstOrDefault();
        }
    }

Link to the implememtation http://iam.colum.edu/datadesign/gbrowser.php?file=/App_code/Repo/CheeseRepo.cs

Now to use the Repo

http://iam.colum.edu/datadesign/classsource/repo/Default.aspx

http://iam.colum.edu/datadesign/gbrowser.php?file=/classsource/repo/Default.aspx.cs

ICheeseRepo db = new TestCheeseRepository();
        gv1.DataSource = db.GetCheeses();
        gv1.DataBind();


You can add LINQ helpers to the class

/// <summary>
    /// Cheese Class for Our Repo
    /// </summary>
    [Table(Name = "Cheese")]
    public class Cheese
    {
        [Column(IsPrimaryKey = true, IsDbGenerated = true, AutoSync = AutoSync.OnInsert)]
        public int CheeseID { get; set; }
        [Column]
        public string CheeseName { get; set; }
        [Column]
        public string CheeseDescription { get; set; }
    }

and then create a new cheese repo

and update your repo initialization

ICheeseRepo db = new CheeseRepository(ConfigurationManager.ConnectionStrings["cheeseConnectionString"].ToString()); 
        gv1.DataSource = db.GetCheeses();
        gv1.DataBind();

LINQ classes in MVC must use the entire namespace

/// <summary>
    /// Cheese Class for Our Repo
    /// </summary>
    [System.Data.Linq.Mapping.Table(Name = "Cheese")]
    public class Cheese
    {
        [System.Data.Linq.Mapping.Column(IsPrimaryKey = true, IsDbGenerated = true, AutoSync = AutoSync.OnInsert)]
        public int CheeseID { get; set; }
        [System.Data.Linq.Mapping.Column]
        public string CheeseName { get; set; }
        [System.Data.Linq.Mapping.Column]
        public string CheeseDescription { get; set; }
    }

Homework

Use the repo pattern to create a repo for you own class. The the class should map to a table in your database. The repo should be able to show items in you db, add items and remove items.

Add the repo to your Web from site and your MVC site. The repose should be able to list items from the DB. Either the MVC site or the WebForms site should be able to add and delete items. I'll give 1 pt extra for updating items and 1 pt for adding/deleting in MVC and Web Forms.