My Technical Lessons

Tuesday, January 13, 2015

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">

<asp:TemplateField>

<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);

Creating a 1st simple MVC application

while i was working on a project where MVC architecture i was completely new to it . i had to refer many e learning materials and finally i started creating an application myself for learning purpose .

the best thing i did was installing VS 2013 ultimate edition .
if you click on New Projects -Web you find the below screen .

Select MVC option from Icons available and click OK

and you will see that your solution is ready with some predefined folder in the solution explorer

The first thing i did was Creating a Controller and Named it as HomeController. this is your controller class . then i created an ActionResult to perform action and navigate to specific View.
namespace WebApplication1.Controllers
{
    public class HomeController : Controller
    {
        //
        // GET: /Home/
        public ActionResult Index()
        {
            return View();
        }
        public ActionResult GotoHome()
        {
            return View("MyHomePage");
        }
    }
}
but then , where is the MyHomePage view ?? i had to create a View as well
and when you create View , it is actually .cshtml page and not a class

placed a simple sentence in the body of the page

@{
    Layout = null;
}

<!DOCTYPE html>

<html>
<head>
    <meta name="viewport" content="width=device-width" />
    <title>MyHomePage</title>
</head>
<body>
    <div>
        Welcome to my first MVC View
    </div>
</body>
</html>

and now ran the solution . but i endedup with some error . i forgot to include controller name and action name in the url and by doing that only i could navigate to desired page

but then this is complicated and wrong way of doing. user will never remember such things
so i had to route is little dynamically . so i went to App_Start-> RouteConfig.cs and placed my navigation details like below

public class RouteConfig
    {
        public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

            routes.MapRoute(
            name: "Home",
            url: "Home",
            defaults: new { controller = "Home", action = "GotoHome", id = UrlParameter.Optional }
        );

            routes.MapRoute(
           name: "Home1",
           url: "",
           defaults: new { controller = "Home", action = "GotoHome", id = UrlParameter.Optional }
       );

            routes.MapRoute(
                 name: "Home2",
                 url: "Home/Home",
                 defaults: new { controller = "Home", action = "GotoHome", id = UrlParameter.Optional }
             );

            routes.MapRoute(
                name: "Default",
                url: "{controller}/{action}/{id}",
                defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
            );
        }
    }

Now See the Home1 route Name. if i dont specify anything in the URL by default it routes to mentioned page where i mentioned the action

Click on f5 and see what you get in the browser

Simple isnt it ?? that's how i started learning MVC .i will keep posting new R&Ds on MVC

Thursday, November 20, 2014

Retrieving Records from MongoDb and Displaying in GridView

We earlier discussed about Inserting the records to mongoDB via C#.
now the Next Step in the CRUD cycle is Read the data from MongoDb and Flash it on the UI screen.
This is how I did :

Drag and Drop the Gridview control and apply the styles which suites your website screen design

Create Connection like Before :
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();

Query the collection and Convert to List

var ShowTasks = collection.FindAllAs<Tasks>().ToList<Tasks>();

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

Binds the Grid

gvShowTasks.DataBind();

Run the Solution.(f5) Bammmm!!! you see that

Tuesday, November 11, 2014

Inserting to MongoDB from C#

I have always been a technology enthusiast and like to implement New things .

When I was introduced to mongo DB, an opensource database tool , I wondered how do I perform basic operations thru .Net .

Hence I created a simple application .

Note : Mongo DB is NoSQL database and not Relational Database Like MSSQL or Oracle.

How I did it .

1. Add MongoDb Dll Reference.

using MongoDB.Bson;

1. using MongoDB.Driver;

2. In the Button Click Event Create Mongo Connection

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

3. Get Database name

MongoServer ms = monClient.GetServer();

ms.Connect();

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

Get Collections(tables)

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

Add a new class similar to the structure u want the schema to be

public class NewProjects

{

public NewProjects()

{

// TODO: Add constructor logic here

}

public string ProjectName { get; set; }

public string ServiceName { get; set; }

public string DescriptionName { get; set; }

}

Assign Values to each field (Binding the values from Front End )

NewProjects proj=new NewProjects();

proj.ProjectName=txtProjName.Text;

proj.ServiceName=txtServiceName.Text;

proj.DescriptionName=txtdesc.Text;

Finally Hit Insert Command

collection.Insert(proj);

View the Result in the backend database

Observe that Unique ID is automatically Created .

Values Passed from Front End

PS: I know you may find it little strange to read Json like Documents(records) because Mongodb stores it in json format . so I have converted these documents from Json like structure to Table format

Here we go

This application was build with Bootstrap JS

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