Problem:

Recently one of my friend was needed only first three rows of data table and so he asked me and I have multiple solutions for that. So thought it would be great idea to share with you guys.

Possible Solutions to problem:

There are two ways to solve this problem.

1. With normal for loop
2. With lamda expression and linq

1. With normal for loop:

Following is code from where we can get 3 rows of data table.

Continue reading →

One of my friend was having problem in Entity framework and stored procedure output parameter. He was confused how to use output parameter with stored procedures.So I did some search on internet and I found a great way to use output parameter so I thought I should write a blog post for the same. So in this blog post I am going to explain you how we can use output parameter of entity framework.

So let’s start coding for that.For demo, I have create a table called ‘Customer’ which contains just two columns CustomerId and CustomerName. Following is the script for that.

/****** Object:  Table [dbo].[Customer]    Script Date: 09/09/2011 00:18:33 ******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[Customer](
    [CustomerId] [int] NOT NULL,
    [CustomerName] [nvarchar](50) NOT NULL,
 CONSTRAINT [PK_Customer] PRIMARY KEY CLUSTERED 
(
    [CustomerId] 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

Now as our table are ready. Let’s create a stored procedure which will return the number of records as output parameter. Following is script for that.

/****** Object:  StoredProcedure [dbo].[esp_GetCustomerCount]    Script Date: 09/09/2011 00:20:21 ******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE PROCEDURE [dbo].[esp_GetCustomerCount]
    @CustomerCount INT OUTPUT
AS
    select @CustomerCount=COUNT(customerId) from Customer
GO

Now our database part is ready so its time to create a entity model. So first I have created a console application and I added a new entity model via project-> right click-> Add new item and selected ADO.NET Entity Model like following.



Once I clicked add a wizard will start asking for choosing model contents like following.



Here I have selected Generate from database and clicked next it will ask for connection string. I have selected connection string and click next it will ask to select object of database. Here I have selected tables and  stored procedure which we have created earlier like following.



Now once we have done our model creation its time to create a function import for store procedure. So do that we need to first open Experiment.edmx in visual studio like below.



Once you click Model browser it will  reopen model browser in right side of your edmx like following.



Now in your store you need to expand store part and select stored procedure and click Add function import like following to create function for stored procedure.



Once you click Add function import a dialog box will open to select stored procedure and return type like following.




Here I have changed name of function called ‘GetCustomerCount’ now once you click OK it will create a function called ‘GetCustomerCount’ in entity framework model. Now its time to use that in code. Following is the code from where can find the output parameter value.

using System;

namespace ExperimentConsole
{
    class Program
    {
        static void Main(string[] args)
        {
            using (ExperimentEntities myContext = new ExperimentEntities())
            {
                System.Data.Objects.ObjectParameter output = new System.Data.Objects.ObjectParameter("CustomerCount", typeof(int));
                myContext.GetCustomerCount(output);
                Console.WriteLine(output.Value);
            }
        }
    }
}

Here in above code you can see that I have created a object parameter and passed that to function as output parameter is there. Once this function will complete execution it will return value and you can get value with .value property. I have printed that in console application. Following is the output as expected as I have added four records in database.



So that’s it. It’s very easy to use output parameter. Hope you liked it. Stay tuned for more. Till then happy programming.. Namaste!!

Windows Azure table storage provides two kind of storage 1) SQL Azure and other one is 2) Table,queue,blob and other storage like drives etc. In this blog post I am going to explain Table storage in details.

What is Windows Azure Table Storage:

Windows Azure table storage is a service provided by Azure platform to store data in form relational tables in windows azure storage instead of normal RDBMS System. It is a structured storage provided by Azure platform. The table storage which you create with windows azure is Unique. An account of windows azure can have any number of table storage.

Table Storage in details:

There are three important aspects when you deal with windows azure table services. Table,Entities and Properties. Here table is similar to storing data in spread sheet or storing in table with relational databases. Entity represents particular row in the table and property represents a particular column or cell in row. There are three system properties of each entity.

1. Partition Key
2. Row Key
3. Time Stamp

Partition Key:

The partition key is a unique key value that is used to group, or partition, related data on same storage node. As we all know that internally data will stored in hard disks in table storage so whenever your data grows then at that time your data may be partitioned into multiple hard drives. At that time this partition key will keep all the data on the same storage nodes. So partition key is used to organize data in storage.

Row Key:

Row key uniquely identifies a specific entities on a partition. Different partition keys may share the same row key, but the same partition may not have two entities with the same row key.The Row Key property is optional and may also be an empty string if all that is needed for uniqueness is the Partition Key value
The PartitionKey and RowKey properties both have String values (up to 1KB in size) and together they form a unique primary key for an entity in a table.

TimeStamp:

Time stamp property has a DateTime value maintained by the Windows Azure Table System to facilitate optimistic concurrency.

Column Types in Table Storage:

Table storage in windows azure support following types of columns.

1. byte[]
2. bool
3. DateTime
4. double
5. Guid
6. Int32 or Int
7. Int64 or long
8. String.

In next post I will create application for table storage. That’s it. Hope you like it. Stay tuned for more.. Till then happy programming..

In today’s post I am going to explain some of the important attributes in EFCodeFirst. Whey you do scaffolding with ASP.NET MVC this all attributes are where much important. So Let’s explore all the attributes.

Key Attribute:

When you put this attribute in the class it tell that this property is part of the primary key and If you use code first when its create table based on this entity then it will be a part of primary key of table. Here is the sample example of that.

[Key]

public int ArticleId { get; set; }

Here article ID will act as primary key.

Foreign Key Attribute:

This attribute is very useful when you deal with interrelated tables You can specify the column in entity which is foreign key for that Like following.

[ForeignKey("CategoryId")]

public ICollection<Category> Categories { get; set; }

In above example CategoryId is a foreign key of category table to article table.

ScaffoldColumn Attribute:

When you Scaffold your application with ASP.NET MVC scaffold feature or dynamic data with asp.net webforms this attribute will tell that this column need to have field for that. You can write that column like following.

[ScaffoldColumn(false)]

public int ArticleId { get; set; }

Here it will tell article id will not have UI in scaffoling.

StringLength Attribute:

This attribute is used to specify the maximum length of a string. This attribute is very usefull in validation and other stuff. This attribute only applied to the Stringlength property like following.

[StringLength(512)]

public string Title { get; set; }

Here in the above code it tell that title could not have more then 512 character string.

There lots of other attributes also. I will blog about it in future posts. Hope you liked this. Stay tuned for more..Happy Programming.

I have been playing with Micro ORMs as this is very interesting things that are happening in developer communities and I already liked the concept of it. It’s tiny easy to use and can do performance tweaks. PetaPoco is also one of them I have written few blog post about this. In this blog post I have explained How we can use the PetaPoco with stored procedure which are having parameters. I am going to use same Customer table which I have used in my previous posts. For those who have not read my previous post following is the link for that.

Get started with ASP.NET MVC and PetaPoco
PetaPoco with stored procedures

Now our customer table is ready. So let’s Create a simple process which will fetch a single customer via CustomerId. Following is a code for that.

CREATE PROCEDURE mysp_GetCustomer
 @CustomerId as INT
AS
SELECT * FROM [dbo].Customer where  CustomerId=@CustomerId

Now we are ready with our stored procedures. Now lets create code in CustomerDB class to retrieve single customer like following.

using System.Collections.Generic;

namespace CodeSimplified.Models
{
  public class CustomerDB
  {
      public IEnumerable<Customer> GetCustomers()
      {
          var databaseContext = new PetaPoco.Database("MyConnectionString");
          databaseContext.EnableAutoSelect = false;
          return databaseContext.Query<Customer>("exec mysp_GetCustomers");

      }
      public Customer GetCustomer(int customerId)
      {
          var databaseContext = new PetaPoco.Database("MyConnectionString");
          databaseContext.EnableAutoSelect = false;
          var customer= databaseContext.SingleOrDefault<Customer>("exec mysp_GetCustomer @customerId",new {customerId});
          return customer;
      }
  }
}

Here in above code you can see that I have created a new method call GetCustomer which is having customerId as parameter and then I have written to code to use stored procedure which we have created to fetch customer Information. Here I have set EnableAutoSelect=false because I don’t want to create Select statement automatically I want to use my stored procedure for that. Now Our Customer DB class is ready and now lets create a ActionResult Detail in our controller like following

using System.Web.Mvc;

namespace CodeSimplified.Controllers
{
  public class HomeController : Controller
  {
      public ActionResult Index()
      {
          ViewBag.Message = "Welcome to ASP.NET MVC!";

          return View();
      }

      public ActionResult About()
      {
          return View();
      }

      public ActionResult Customer()
      {
          var customerDb = new Models.CustomerDB();
          return View(customerDb.GetCustomers());
      }
      public ActionResult Details(int id)
      {
          var customerDb = new Models.CustomerDB();
          return View(customerDb.GetCustomer(id));
      }
  }
}

Now Let’s create view based on that ActionResult Details method like following.



Now everything is ready let’s test it in browser. So lets first goto customer list like following.



Now I am clicking on details for first customer and Let’s see how we can use the stored procedure with parameter to fetch the customer details and below is the output.



So that’s it. It’s very easy. Hope you liked it. Stay tuned for more..Happy Programming.

Visual studio 2010 Ultimate is great IDE(Integrated Development Environment) and I am loving more and more whenever I found some thing new. While doing some Code and Review and other stuff with Visual Studio 2010 I have found one of most interesting feature in Visual Studio 2010 called “Called Hierarchy”.You can navigate your code better with the Call Hierarchy feature in Visual Studio 2010.
To check out let’s Create a sample asp.net MVC application like following .



After creating a ASP.NET MVC 2 application it will create a basic simple application and we can run it and We have two views like home and about. We will check few code with Call Hirarchy. We can enable Call hierarchy window with two way one from the View->View Call Hierarchy like following or you can also use the shortcut Ctrl+Alt+K.

 

Now lets check the Account Controller-> Logon Action Result with call hierarchy You can also enable call hierarchy with selecting the Logon action and right click –> View Call Hierarchy like following or You can use the Shortcut for that like Ctrl + K,Ctrl + T.

 

Once you click the call Hierarchy It will open the code that is called logon and also call made from the logon method like below.



One you expand the both ‘Call To LogOn’ and ‘Calls from LogOn’ you can see all the calls Since there is no call for Logon on asp.net mvc sample application it will say but you can see calls made from it like following.



And on double click on any method or property will navigate you that code. Like I have double clicked the IsNullOrEmpty I have navigated to string class with that property.



That’s it. So you can see its a great way to navigate code for code review and code inspection. Hope you liked it.. Stay tuned for more.. Happy Programming..

Microsoft is organizing the windows Azure camp in various cities of India. It’s a great chance to learn new things about Microsoft Windows Azure. So If you want to be part of that then you must register in this event. Following are date and cities information.

Ahmedabad- 10th April 2011 now postponed to 30th April( I will be there at 30th April 2011)
Banglore-30th April 2011
Chennai-9th April 2011
Delhi-10th April 2011
Hyderabad-10th April 2011
Kolkata-10th April 2011
Mumbai-9th April 2011
Mysore-10th April 2011
Pune –10th April 2011
Triavndrum –30th April 2011

Here is the link from where you can register for that event
http://www.microsoft.com/india/azurecontest/azurecamp.aspx

See you guys there.. Stay tuned for more..

Linq operator provides great flexibility and easy way of coding. Let’s again take one more example of distinct operator. As name suggest it will find the distinct elements from IEnumerable. Let’s take an example of array in console application and then we will again print array to see is it working or not. Below is the code for that. In this application I have integer array which contains duplicate elements and then I will apply distinct operator to this and then I will print again result of distinct operators to actually see whether its working or not.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Experiment
{
   class Program
   {
       static void Main(string[] args)
       {
           int[] intArray = { 1, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5 };
           var uniqueIntegers = intArray.Distinct();
           foreach (var uInteger in uniqueIntegers)
           {
               Console.WriteLine(uInteger);
           }
           Console.ReadKey();

       }
   }
}

Below is output as expected..

That’s cool..Stay tuned for more.. Happy programming.

Technorati Tags: Linq,Distinct

CodeProject

I have used data source control many times and its great it provides us great features for declarative binding. LinqDataSource Control is a great control and it allows us to bind linq queries without writing any code declaratively. Let’s create a example in that example I am not going to write a single line of code and we are going to create view,Update and Delete functionality.

So first we need a table which will have data. So, I am going to use the same table which I have used in my old posts. Below is the table structure for this example.

Let’s insert some data for that table structure. I have already inserted it in previous example. Just like below.

Now, To bind a linqdatasource we need a Linq-To-SQL Data context class Let’s create it via Project->Right Click->Add New Item –>Go to data tab->Linq-To-SQL classes Just like following.

After that I have just dragged user data to my data context just like following.

After creating Our Linq-To-SQL Classes Let’s just Add the A grid View control to my default.aspx page and apply some default format like this.

Now Let’s add a LinqDataSource from the toolbox like following.

Now select the data source and click configure data source as we can see as below.

After clicking on the Configure Data source a wizard will appear which will allow us to select Linq-to-SQL Context class just like following.

After clicking on next it will allow us to select the Linq-To-SQL Table. In our case it is a Users table so select user table just like following and select * for all columns.

Click finish now our Linq Data Source is Ready Now select the grid view and select Linq Data source we just created like below.

Now our grid view is ready We just need to select Enable Sorting and Enable Paging to give default sorting and paging functionality to grid view. Now do to aspx file and you will see that grid view control is created. I have set two more properties AutoGenerateDeleteButton and AutoGenerateEditButton property of grid view to true as we need to create update and delete functionality also. Just like below.

<asp:GridView ID="GridView1" runat="server" CellPadding="4" ForeColor="#333333"
GridLines="None" AllowPaging="True" AllowSorting="True"
AutoGenerateColumns="False" DataSourceID="LinqDataSource1"
AutoGenerateDeleteButton="True" AutoGenerateEditButton="True"
DataKeyNames="UserId" >
  <AlternatingRowStyle BackColor="White" />
  <Columns>
     <asp:BoundField DataField="UserId" HeaderText="UserId"
            SortExpression="UserId" ReadOnly="True" />
     <asp:BoundField DataField="UserName" HeaderText="UserName"
            SortExpression="UserName" />
     <asp:BoundField DataField="FirstName" HeaderText="FirstName"
            SortExpression="FirstName" />
     <asp:BoundField DataField="LastName" HeaderText="LastName"
            SortExpression="LastName" />
   </Columns>
   <EditRowStyle BackColor="#2461BF" />
   <FooterStyle BackColor="#507CD1" Font-Bold="True"
    ForeColor="White" />
   <HeaderStyle BackColor="#507CD1" Font-Bold="True"
 ForeColor="White" />
   <PagerStyle BackColor="#2461BF" ForeColor="White"
 HorizontalAlign="Center" />
   <RowStyle BackColor="#EFF3FB" />
   <SelectedRowStyle BackColor="#D1DDF1" Font-Bold="True"
    ForeColor="#333333" />
   <SortedAscendingCellStyle BackColor="#F5F7FB" />
   <SortedAscendingHeaderStyle BackColor="#6D95E1" />
   <SortedDescendingCellStyle BackColor="#E9EBEF" />
   <SortedDescendingHeaderStyle BackColor="#4870BE" />
</asp:GridView>

Then go to Linq Data source and set EnableDelete and EnableUpdate property to true as we need this functionality. Just like following.

<asp:LinqDataSource ID="LinqDataSource1" runat="server"
  ContextTypeName="Blog.MyBlogDataContext"
  EntityTypeName="" TableName="Users"
  EnableDelete="True" EnableUpdate="True">
</asp:LinqDataSource>

That’s it now everything is ready lets run the example and see how its works here is the update example and its working fine as should.

So It’s very easy to create this kind of functionality. Hope this help you.. Happy Programming..

Technorati Tags: Linq-To-Sql,LinqDataSource,Linq,ASP.NET,Datasource

C# 4.0 has one new cool features which is the named parameter. Suppose you have so many parameter in function and when you call them its hard to remember the sequence of the code now with the named parameter you can have name of the parameter with value like Parameter:value and one another cool feature of the name parameter is the you don't need to pass the parameter in exact sequence. Let see the following example

Code Snippet

1. protected void Page_Load(object sender, EventArgs e)
2. {
3. foreach (int i in Square( max:10,min:1))
4. {
5. Response.Write(i.ToString() + " ");
6. }
7. }
8. 
   
9. public static IEnumerable<int> Square(int min, int max)
10. {
11. for (int i = min; i < max; i++)
12. {
13. yield return i*i;
14. }
15. }
16. 
    

In above example I am having a function called square with two parameter min and max and having a function which will return the square of the given range between min and max. See the for each loop carefully. I have named parameters and another thing you will notice that i have changed the sequence of parameter but still its working fine. So this is a very cool new feature from the C# 4.0.

Happy Programming...

Technorati Tags: C#4.0,ASP.NET 4.0

Microsoft visual studio express editions are light weight IDE provided free by Microsoft and also having almost all the functionality of its big brother Microsoft Visual Studio Professional edition except few. My pc is bit old now Its P4 and its having only 1gigs of ram so the express edition are the best suited for pc like mine. Microsoft has recently provided the beta 2 version of Microsoft new generation IDE called Visual Studio Twenty Ten(2010).

There are lots of changes from visual studio 2008 express edition and Microsoft Visual Studio 2010 Express edition. The first changes you will notice is the brand new splash screen and brand new colored logo for visual studio.

Another thing you will notice is the look and fill of IDE. It all looks like blue every where. Its is best suited for the Microsoft forthcoming operating system Microsoft Windows 7.

Another the difference is the create new project window which is bit stylish and having more options compare the to the visual studio 2008. There are two new things in new project dialog the first one the windows azure tools which is Microsoft's new steps towards the could computing(I will blog about this later one). and another thing is the Silver light application option. Now you can create three kind of application with the Microsoft SilverLight Application

1. Silverlight Application
2. Silverlight Navigation Application
3. Silverlight class library

Another difference is the default font for the IDE earlier it was Courier New and now its Consolas which is the next generation programming font. Which is more visual than the other fonts.

Another major difference is when you create a asp.net web application then its now having more default folders compare to visual studio 2008. There are site.master is also there and some default style sheet just like asp.net mvc applications. You will have default login control like asp.net mvc application. There are two more folder scripts and styles. In style you will have default style sheet for the application. Another folder is for the scripts which are having default JQuery as per earlier announcement Microsoft and JQuery will go together.

Another new things in Microsoft Visual Studio 2010 Visual Web Developer Expression edition is the Tool Setting menu which are having three setting by default.

1. Basic Settings
2. Code Optimized
3. Expert Settings.

All the three option will have different setting for solution explorer and all other stuff. Another new thing is visual web developer 2010 express edition having multi monitor support which is not there in earlier express editions.Visual web developer express also having windows presentation foundation code editor.

Another cool feature is the maximized windows in design view now you will have whole window is maximized in design view hiding other windows. So you visually look all the control more better. Another cool thing is the percentage dropdown through which you can set all screen by percentage as per your requirement.

There are lots of more features like Improved css compatibility,HTML and Javascript snippets,support for asp.net mvc application and support for multi target etc. I will blog about each feature in much more detail. T

If you still not downloaded the future version of visual studio express edition 2010 then you can download it from the following link.

http://www.microsoft.com/express/future/default.aspx

Technorati Tags: Microsoft Visual Web Developer Express Edition 2010,ASP.NET 4.0,Microsoft Express edition