Entity FrameWork With MVC5 Part 4 (Delete)

we earlier saw how easy and efficient it was to add a record and read a record .
same way we can do delete operation

Note : we first find the id of the record to be deleted and then hit delete . 

so below are the action result to delete the records (get and post methods)

[HttpGet]

        public ActionResult Delete(int id)

        {

            ProjectWBSContext pwbs = new ProjectWBSContext();

            if (id == null)

            {

                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);

            }

            Projects projects = pwbs.Projects.Find(id);

            if (projects == null)

            {

                return HttpNotFound();

            }

            return View(projects);

        }

        ///Project/Delete/2

        [HttpPost, ActionName("Delete")]

        public ActionResult DeleteConfirmed(int id)

        {

          

                ProjectWBSContext pwbs = new ProjectWBSContext();

                Projects projects = pwbs.Projects.Find(id);

                pwbs.Projects.Remove(projects);

                pwbs.SaveChanges();

                return RedirectToAction("Index");

         

           

        }

Create a view and then hit run . you will see the UI to delete the records 

Deleting MongoDB Records using Gridview

So far we have seen select and insert Operations .
we now see how we can perform delete operation.
Place a check box control in the gridview like below

<asp:GridView ID="gvShowTasks" runat="server" CssClass="table table-striped table-bordered table-hover" OnRowCancelingEdit="gvShowTasks_RowCancelingEdit" OnRowEditing="gvShowTasks_RowEditing"  DataKeyNames="Id" OnRowUpdating="gvShowTasks_RowUpdating">

                   <Columns>

                       <asp:TemplateField>

                           <ItemTemplate>

                               <asp:CheckBox ID="chk" runat="server" />

                           </ItemTemplate>

                       </asp:TemplateField>

                       <asp:CommandField ShowEditButton="true" />

                   </Columns>

               </asp:GridView>

on the Code Behind Place the below code in the Delete button click event

protected void btnDelete_Click(object sender, EventArgs e)

    {

        MongoClient monClient = new MongoClient("mongodb://localhost");

        MongoServer ms = monClient.GetServer();

        ms.Connect();

        MongoDatabase db = ms.GetDatabase("testdb");

        MongoCollection collection = db.GetCollection<Tasks>("Tasks");

        Tasks tsk = new Tasks();

        foreach (GridViewRow gvr in gvShowTasks.Rows)

        {

            var rowIndex = gvr.RowIndex;

            var TaskID = gvShowTasks.DataKeys[rowIndex].Values["Id"].ToString();// capturing object id for deletion

            var rowVal = gvShowTasks.Rows[rowIndex].Cells[3].Text;

            CheckBox chk = (CheckBox)gvr.FindControl("chk");

          if (chk.Checked)

          {

              ObjectId bsonId=(ObjectId.Parse(TaskID));//converting string to object id

              IMongoQuery query = Query.EQ("_id", bsonId);

              collection.Remove(query);

             

          }

           

           

        }

        var ShowTasks = collection.FindAllAs<Tasks>().ToList<Tasks>(); //Queries the tasks collection and Converts to List           

        gvShowTasks.DataSource = ShowTasks;//Set the List as Data source 

        gvShowTasks.DataBind();//Binds the Grid

    }

 Run the solution and there you go .. whichever row you have selected , on click of delete button the same row will be deleted . you can also customise your delete query in the statement
  IMongoQuery query = Query.EQ("_id", bsonId);