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Showing posts with label ASP.Net MVC. Show all posts
Showing posts with label ASP.Net MVC. Show all posts

Tuesday, August 2, 2016

ASP.Net MVC - ViewBag, ViewData and Tempdata

By Francis   Posted at   9:08 PM   ASP.Net MVC No comments



                  As an ASP.Net MVC developer, you may frequently involved with these terms like Tempdata, viewdata and viewbag. In this post, I’m going to discuss about what are they and what are the main difference between them.

ViewBag:

  1. ViewBag is dynamic in nature.
  2. There is no type casting needed.
  3. Life time lasts only for the current request.

View Data:
  1. ViewData is stored as a dictionary. You can store a value using a key.
  2. Type casting is needed, when you retrieve.
  3. Life time lasts only for the current request.

Tempdata:

  1. It’s also store the value using key.
  2. Need type casting when the stored value retrieved.
  3. The life time of tempdata is little bit tricky. It will be available till you read it first time. After you read it, it will be marked for deletion. So in the next request, it won’t available.  However, you can extend it’s life time by using keep and peek method.

Hope this helps!

Friday, December 25, 2015

CRUD Operation - ASP.Net MVC with ADO.Net

By Francis   Posted at   6:58 AM   CRUD No comments
                                   
                                In this post, I’m going to discuss about the CRUD(Create, Read, Update and Delete) Operation in an ASP.Net MVC application by using raw ADO.Net. Most of the new learners, who started to learn MVC asked this frequently. That’s the main reason behind this tutorial.

Configuration:
For this particular application, I have used the below configuration:
1. Visual Studio 2015
2. SQL Server 2008
In order to keep my hand clean, I have used a simple table to do the CRUD operation.

Step 1:
Execute the below script on your DB

SET ANSI_NULLS ON 
GO

SET QUOTED_IDENTIFIER ON 
GO

SET ANSI_PADDING ON 
GO

CREATE TABLE [dbo].[tblStudent]( 
    [student_id] [int] IDENTITY(1,1) NOT NULL, 
    [student_name] [varchar](50) NOT NULL, 
    [stduent_age] [int] NOT NULL, 
    [student_gender] [varchar](6) NOT NULL, 
CONSTRAINT [PK_tblStudent] PRIMARY KEY CLUSTERED 
( 
    [student_id] ASC 
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY] 
) ON [PRIMARY]

GO

SET ANSI_PADDING OFF 
GO


Step 2:
Create an “Empty” ASP.Net.MVC 4 application in Visual Studio 2015. Empty-MVC-Project

Step 3:
Add an “Empty” Controller by right clicking on the “Controller” folder select “Add” then select “Controller..”. In the popup select “MVC 5 Controller” then click “Add”. In the next popup you should give the name of the as “CRUDController”.
Add-Empty-Controller
After add the controller, you may noticed as per the “convention” in ASP.Net MVC under the “Views” folder, a new folder named “CRUD” also created.
Convention-Over-Configuration

Step 4:
Our DB access code are going to be placed inside the “Models” folder. Model is just a “Class” file.  So we are going to create a Model class for our purpose as below:
1. Right click on the “Model” folder. In the context menu select “Add” then choose “New item..”.
2. In the popup, select “Code” then choose “Class” and name the class file as “CRUDModel” then click “Add”. That’s all!
Add-Empty-Model
Step 5:
Till now we created classes for “Controller” and “Model”. We didn’t create any views till now. In this step we are going to create a view, which is going to act as a “home” page for our application. In order to create the view:
1. Right click on the “CRUD” folder under the “Views” folder in the context menu select “Add” then choose “View..”.
2. In the popup, give “View Name” and uncheck the “Use a layout page” checkbox. Finally click “Add” button.
Add-View
Step 6:
We don’t have a controller named “Default”, which is specified in the “RouteConfig.cs” file. We need to change the controller’s name as “CRUD”, in the default route values.

Route.config:

using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
using System.Web.Mvc; 
using System.Web.Routing;

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

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


After the above change, just press F5 in visual studio, to verify that our application works fine without any error.
Step 7:
In order to achieve the complete CRUD operation, I’m going to add number of views as described in the Step 5. Here is the complete list of views and it’s purpose.
View Purpose
Home.cshtml This is the default view. Loaded when the application
launched. Will display all the records in the table
Create.cshtml Displays control’s to insert the record. Will be rendered
when the “Add New Record” button clicked on
the “Home.cshtml” view.
Edit.cshtml Displays control’s to edit the record. Will be rendered
when the “Edit” button clicked on the “Home.cshtml” view.

Step 8:
The model class, contains the all the “Data Access” logic. In other words, it will interact with Database and give it back to “View” thru “Controller”.


using System.Data; 
using System.Data.SqlClient;

namespace MVCWithADO.Models 
{ 
    public class CRUDModel 
    { 
        ///  
        /// Get all records from the DB 
        ///  
        /// Datatable 
        public DataTable GetAllStudents() 
        { 
            DataTable dt = new DataTable(); 
            string strConString =@"Data Source=WELCOME-PC\SQLSERVER2008;Initial Catalog=MyDB;Integrated Security=True"; 
            using (SqlConnection con = new SqlConnection(strConString)) 
            { 
                con.Open(); 
                SqlCommand cmd = new SqlCommand("Select * from tblStudent", con); 
                SqlDataAdapter da = new SqlDataAdapter(cmd); 
                da.Fill(dt); 
            } 
            return dt; 
        }

        ///  
        /// Get student detail by Student id 
        ///  
        ///  
        ///  
        public DataTable GetStudentByID(int intStudentID) 
        { 
            DataTable dt = new DataTable();

            string strConString = @"Data Source=WELCOME-PC\SQLSERVER2008;Initial Catalog=MyDB;Integrated Security=True";

            using (SqlConnection con = new SqlConnection(strConString)) 
            { 
                con.Open(); 
                SqlCommand cmd = new SqlCommand("Select * from tblStudent where student_id=" + intStudentID, con); 
                SqlDataAdapter da = new SqlDataAdapter(cmd); 
                da.Fill(dt); 
            } 
            return dt; 
        }

        ///  
        /// Update the student details 
        ///  
        ///  
        ///  
        ///  
        ///  
        ///  
        public int UpdateStudent(int intStudentID, string strStudentName, string strGender, int intAge) 
        { 
            string strConString = @"Data Source=WELCOME-PC\SQLSERVER2008;Initial Catalog=MyDB;Integrated Security=True";

            using (SqlConnection con = new SqlConnection(strConString)) 
            { 
                con.Open(); 
                string query = "Update tblStudent SET student_name=@studname, student_age=@studage , student_gender=@gender where student_id=@studid"; 
                SqlCommand cmd = new SqlCommand(query, con); 
                cmd.Parameters.AddWithValue("@studname", strStudentName); 
                cmd.Parameters.AddWithValue("@studage", intAge); 
                cmd.Parameters.AddWithValue("@gender", strGender); 
                cmd.Parameters.AddWithValue("@studid", intStudentID); 
                return cmd.ExecuteNonQuery(); 
            } 
        }

        ///  
        /// Insert Student record into DB 
        ///  
        ///  
        ///  
        ///  
        ///  
        public int InsertStudent(string strStudentName, string strGender, int intAge) 
        { 
            string strConString = @"Data Source=WELCOME-PC\SQLSERVER2008;Initial Catalog=MyDB;Integrated Security=True";

            using (SqlConnection con = new SqlConnection(strConString)) 
            { 
                con.Open(); 
                string query = "Insert into tblStudent (student_name, student_age,student_gender) values(@studname, @studage , @gender)"; 
                SqlCommand cmd = new SqlCommand(query, con); 
                cmd.Parameters.AddWithValue("@studname", strStudentName); 
                cmd.Parameters.AddWithValue("@studage", intAge); 
                cmd.Parameters.AddWithValue("@gender", strGender); 
                return cmd.ExecuteNonQuery(); 
            } 
        }

        ///  
        /// Delete student based on ID 
        ///  
        ///  
        ///  
        public int DeleteStudent(int intStudentID) 
        { 
            string strConString = @"Data Source=WELCOME-PC\SQLSERVER2008;Initial Catalog=MyDB;Integrated Security=True";

            using (SqlConnection con = new SqlConnection(strConString)) 
            { 
                con.Open(); 
                string query = "Delete from tblStudent where student_id=@studid"; 
                SqlCommand cmd = new SqlCommand(query, con); 
                cmd.Parameters.AddWithValue("@studid", intStudentID); 
                return cmd.ExecuteNonQuery(); 
            } 
        } 
    } 
}




Controller:
Controller

using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
using System.Web.Mvc; 
using System.Data; 
using System.Data.SqlClient; 
using MVCWithADO.Models; 
namespace MVCWithADO.Controllers 
{ 
    public class CRUDController : Controller 
    { 
        ///  
        /// First Action method called when page loads 
        /// Fetch all the rows from DB and display it 
        ///  
        /// Home View 
        public ActionResult Index() 
        { 
            CRUDModel model = new CRUDModel(); 
            DataTable dt = model.GetAllStudents(); 
            return View("Home",dt); 
        }

        ///  
        /// Action method, called when the "Add New Record" link clicked 
        ///  
        /// Create View 
        public ActionResult Insert() 
        { 
            return View("Create"); 
        }

        ///  
        /// Action method, called when the user hit "Submit" button 
        ///  
        /// Form Collection  Object 
        /// Used to differentiate between "submit" and "cancel" 
        ///  
        public ActionResult InsertRecord(FormCollection frm, string action) 
        { 
            if (action == "Submit") 
            { 
                CRUDModel model = new CRUDModel(); 
                string name = frm["txtName"]; 
                int age = Convert.ToInt32(frm["txtAge"]); 
                string gender = frm["gender"]; 
                int status = model.InsertStudent(name, gender, age); 
                return RedirectToAction("Index"); 
            } 
            else 
            { 
                return RedirectToAction("Index"); 
            } 
        }

        ///  
        /// Action method called when the user click "Edit" Link 
        ///  
        /// Student ID 
        /// Edit View 
        public ActionResult Edit(int StudentID) 
        { 
            CRUDModel model = new CRUDModel(); 
            DataTable dt = model.GetStudentByID(StudentID); 
            return View("Edit", dt); 
        }

        ///  
        /// Actin method, called when user update the record or cancel the update. 
        ///  
        /// Form Collection 
        /// Denotes the action 
        /// Home view 
        public ActionResult UpdateRecord(FormCollection frm,string action) 
        { 
            if (action == "Submit") 
            { 
                CRUDModel model = new CRUDModel(); 
                string name = frm["txtName"]; 
                int age = Convert.ToInt32(frm["txtAge"]); 
                string gender = frm["gender"]; 
                int id = Convert.ToInt32(frm["hdnID"]); 
                int status = model.UpdateStudent(id, name, gender, age); 
                return RedirectToAction("Index"); 
            } 
            else 
            { 
                return RedirectToAction("Index"); 
            } 
        }

        ///  
        /// Action method called when the "Delete" link clicked 
        ///  
        /// Stutend ID to edit 
        /// Home view 
        public ActionResult Delete(int StudentID) 
        { 
            CRUDModel model = new CRUDModel(); 
            model.DeleteStudent(StudentID); 
            return RedirectToAction("Index"); 
        } 
    } 
}



Views:
Create.cshtml


<!DOCTYPE html>

<html>    

<head>     

    <meta name="viewport" content="width=device-width" />     

    <title>Insert</title>     

</head>     

<body>     

    <form id="frmDetail" method="post" action="@Url.Action("InsertRecord")">     

        Enter Name:<input name="txtName" />     

        <br />     

        Enter Age:<input name="txtAge" />     

        <br />     

        Select Gender: <input type="radio" name="gender" value="male" checked>Male     

        <input type="radio" name="gender" value="female">Female     

        <br />     

        <input type="submit" value="Submit" name="action" />     

        <input type="submit" value="Cancel" name="action" />     

    </form>     

</body>     

</html>    

Home.cshtml:
@using System.Data    

@using System.Data.SqlClient     

@model System.Data.DataTable     

@{     

    Layout = null;     

}

<!DOCTYPE html>

<html>    

<head>     

    <meta name="viewport" content="width=device-width" />     

    <title>Home</title>     

</head>     

<body>     

    <form method="post" name="Display">     

        <h2>Home</h2>     

        @Html.ActionLink("Add New Record", "Insert")     

        <br />     

        @{     

            if (Model.Rows.Count > 0)     

            {     

                <table>     

                    <thead>     

                        <tr>     

                            <td>     

                                Student ID     

                            </td>     

                            <td>     

                                Name     

                            </td>     

                            <td>     

                                Age     

                            </td>     

                            <td>Gender</td>     

                        </tr>     

                    </thead>     

                    @foreach (DataRow dr in Model.Rows)     

                    {     

                        <tr>     

                            <td>@dr["student_id"].ToString()  </td>     

                            <td>@dr["student_name"].ToString()  </td>     

                            <td>@dr["student_age"].ToString()  </td>     

                            <td>@dr["student_gender"].ToString()  </td>     

                            <td>@Html.ActionLink("Edit ", "Edit", new { StudentID = dr["student_id"].ToString() })</td>     

                            <td>@Html.ActionLink("| Delete", "Delete", new { StudentID = dr["student_id"].ToString() })</td>     

                        </tr>     

                    }

                </table>    

                <br />     

            }     

            else     

            {     

                <span> No records found!!</span>     

            }     

            }

    </form>    

</body>     

</html>     

Edit.cshtml
@using System.Data    

@using System.Data.SqlClient     

@model System.Data.DataTable     

@{     

    ViewBag.Title = "EditView";     

}     

<html>     

<head>     

    <script type="text/javascript">     

    </script>     

</head>     

<body>     

    <form id="frmDetail" method="post" action="@Url.Action("UpdateRecord")">     

        Enter Name:<input name="txtName" value="@Model.Rows[0]["student_name"]" />     

        <br />     

        Enter Age:<input name="txtAge" value="@Model.Rows[0]["student_age"]" />     

        <br />     

        Select Gender:

        @if (Model.Rows[0]["student_gender"].ToString().ToLower() == "male")    

        {     

            <input type="radio" name="gender" value="male" checked /> @Html.Raw("Male")     

            <input type="radio" name="gender" value="female" />            @Html.Raw("Female")     

        }     

        else     

        {     

            <input type="radio" name="gender" value="male">  @Html.Raw("Male")     

            <input type="radio" name="gender" value="female" checked />            @Html.Raw("Female")     

        }     

        <input type="hidden" name="hdnID" value="@Model.Rows[0]["student_id"]" />     

        <br />     

        <input type="submit" value="Submit" name="action" />     

        <input type="submit" value="Cancel" name="action"/>     

    </form>     

</body>     

</html>   

Monday, September 7, 2015

How to Hosting Asp.net MVC Web Application in Local Machine?

By Francis   Posted at   2:32 PM   IIS No comments

                     In this post I’m going to discuss about how to host an ASP.Net MVC Application in your  local machine. Most of the steps to deploy a web form application and MVC applications are equivalent.

Prerequisite:

           In order to explain the steps, I assume you have a complete ASP.Net MVC Application that is ready to build with out any error.

Step 1:

Publish you MVC application in a local file path, using publish option in Visual Studio.

publishOptionInVS

For this example, I have published my application in the below path like : C:\MVCDemo

ASPNETPublishedFiles

Step 2:

Create a Virtual directory in IIS and mapped the above published file path to it.

MVCAppVirtualDirectory

If you have any doubts in creating virtual directory refer my below blog posts:

Create virtual directory on IIS using Visual Studio.

Create Virtual directory on IIS

Step 3:

You are almost done! The only thing pending is you need to browse the website, that just published. This is where most of the ASP.Net developer (especially who is a newbie to ASP.Net MVC), what they were doing : Expand the Virtual directory –> Views –> Switch to content view –> select the cshtml file –> right click on it and click “Browse”, which throws 404 Error in browser.

BrowseMVCFile

404Error

 

The above issue is common to all ASP.Net developers, who are all comes with ASP.Net  WebForm background. In order to browse the  mvc application, you need to mention the path in the form like “http://localhost/YourControllerName/YourActionMethod", which is the url routing pattern specified by default.

 

ASPNetApplication

 

Hope this helps!

Saturday, December 20, 2014

ASP.Net MVC – Create Custom HTML Helpers

By Francis   Posted at   11:52 AM   Razor No comments
Html Helpers are classes that helps to render HTML controls in Views. We can also create our own HTML Helpers. In this post, I’m going to explain how to create a simple Custom HTML Helper. The main purpose creating custom HTML helper is reuseability.

Step 1:
          Create a static class and add method to it like below.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
namespace MVCTutorial
{
    public static class CustomHTMLHelper
    {
        public static MvcHtmlString ImageLink(string action, string controller, string imgageURL)
        {
            // Create a link with an image
            return MvcHtmlString.Create(String.Format("<a href=\"{1}\\{0}\"> <img src=\"{2}\" /></a>", action, controller, imgageURL));
        }
    }
}

     
Step 2:
          Access the custom helper class in a View.
<!DOCTYPE html>
<html>
<head>
    <meta name="viewport" content="width=device-width" />
    <title>Sample</title>
</head>
<body>
    <div>
        @CustomHTMLHelper.ImageLink("Home","Account","your image url")
    </div>
</body>
</html>


The helper class is static, since it can be called in a easy manner also handy.
Happy coding!

Wednesday, July 31, 2013

ASP.Net MVC - An Introduction

By Francis   Posted at   12:24 PM   MVC 4 comments
What is MVC?
             Several Months ago, I just started to learn new technologies in order to teach other thru a weekly technical session in my current company. So I decide to lean ASP.Net MVC. These points are from my learning.

So what is ASP.Net MVC?
             According to Microsoft, ASP.Net MVC is a new paradigm to design a website using Model, View and Contoller Pattern. The first 3 letters of Model, View and Controller forms the name MVC. However MVC newly introduced in ASP.Net but MVC is not a new framework it has been already used in Java and PHP etc.
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