How to implement the Delete method in the interface and call it in the Controller MVC4

Question

0.00/5 (No votes)

See more:

Hi i want to implement my void Delete method in my DataSource. I've created the Save() method, but struggling with Delete(). I've been searching but still don't know how to do it. Any help.

The interface:

   public  interface IDepartmentDataSource
{
    IQueryable<User> Users { get; }
    IQueryable<Department> Departments { get;}
    IQueryable<Entry> Entries { get; }

    void Delete();
    void Save();

}

DataSource:

public class DepartmentDb : DbContext, IDepartmentDataSource
{
    public DepartmentDb() : base("DefaultConnection")
    {

    }

    public DbSet<User> Users { get; set; }
    public DbSet<Department> Departments { get; set; }
    public DbSet<Entry> Entries { get; set; }


    void IDepartmentDataSource.Save()
    {
        SaveChanges();  
    }

    void IDepartmentDataSource.Delete()
    {

        // What is the logic here?

    }

    IQueryable<Entry> IDepartmentDataSource.Entries
    {
        get { return Entries; }
    }

    IQueryable<Department> IDepartmentDataSource.Departments
    {
        get { return Departments; }
    }

    IQueryable<User> IDepartmentDataSource.Users
    {
        get { return Users; }
    }
}

Posted 29-Sep-14 0:10am

PetarS089

Add a Solution

Comments

Gihan Liyanage 29-Sep-14 6:28am

Do you want delete by user ID ? Or you want to delete Departments by DepID?

PetarS089 29-Sep-14 6:49am

I want to delete Department by Id. I have Department Class that have Id and Department_Name.

2 solutions

Solution 1

you can decorate controller with [HttpPost, ActionName("Delete")]

please refer this link[^]

Posted 29-Sep-14 0:24am

PrakashCs.net

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

nrgjack · Accepted Answer · 2014-09-29T22:30:00

you can use :

C#

void IDepartmentDataSource.Delete(Entry entry) 
{
    Entries.Remove(entry);
}

but may be,
using a repository like below could be better
(a repository that encapsulate every CRUD EF operation)
i would make it in 2 steps :

C#

// this is your EF dbcontext (stndard)
public class DepartmentDb : DbContext
{
    public DepartmentDb() : base("DefaultConnection")
    {

    }

    public DbSet<User> Users { get; set; }
    public DbSet<Department> Departments { get; set; }
    public DbSet<Entry> Entries { get; set; }

}

// your repository
public class DepartmentRepository: IDisposable
{
    protected bool isDisposed = false;
    private DepartmentDb Context { get; set; } 

    // read (public)
    public IQueryable<user> Users { get { return Context.Users; } }
    public IQueryable<department> Departments { get { return Context.Departments; } }
    public IQueryable<entry> Entries { get { return Context.Entries; } }

    public DepartmentRepository() 
    {
         Context = new DepartmentDb();
    }

    // write the same for the others
    public int Insert(User item)
    { 
        Context.Users.Add(item);
        return Context.SaveChanges();
    }

    // write the same for the others
    public int Update(User item)
    { 
        Context.Entry<user>(item).State = EntityState.Modified;
        return Context.SaveChanges();
    }

    // write the same for the others
    public int Delete(User item)
    { 
        Context.Users.Remove(item);
        return Context.SaveChanges();
    }

    protected virtual void Dispose(bool disposing)
    {
	if (isDisposed)
		return;

	if (disposing)
	{
		if (this.Context != null)
		{
			this.Context.Dispose();
			this.Context = null;
		}
	}

	isDisposed = true;
    }

    public void Dispose()
    {
	Dispose(true);
	GC.SuppressFinalize(this);
    }	

}

usage :

C#

using(var repo = new DepartmentRepository())
{
  var u = new User(){Name="Jack"};
  var repo.Insert(u);
  u.Name = "Jim";
  repo.Update(u);
  repo.Delete(u);
}

if you want to read more look for "repository pattern" there are several versions of it

UPDATE :
if you want to write less code ;)
you can write

C#

public interface IDepRepoEntity
{
    // empty
}
public partial class User : IDepRepoEntity {}
public partial class Department: IDepRepoEntity {}
public partial class Entry: IDepRepoEntity {}

than in your repository :

C#

public int Insert<T>(T item) where T : IDepRepoEntity
{
    Context.Set<T>.Add(item);
    return Context.SaveChanges();
}

public int Update<T>(T item) where T : IDepRepoEntity
{
    Context.Entry<T>(item).State = EntityState.Modified;
    return Context.SaveChanges();
}

public int Delete<T>(T item) where T : IDepRepoEntity
{
    Context.Set<T>.Remove(item);
    return Context.SaveChanges();
}