Transactions in WCF

In my previous post i explained, Interview question and few details on WCF. Now in this article i will explain how WCF Transaction protocol.

Transaction is an important factor in any business application which contain CRUD operations. Here in WCF we have TransactionScope class which basically manages the transaction and also detech the transaction scope.

for ex. If your calling multiple methods and if any of method fails, then entire transaction will be rolled back unless its outside boundary of Scope.

WCF supports transaction on below bindings.

 
1.  WSHttpBinding
2.  WSFederationHttpBinding
3.  NetNamedPipeBinding
4.  NetTcpBinding
5.  WSDualHttpBinding


You need to specify the TransactionFlow attribute on all the contracts where it required transaction to be handled. where we have to specified that transaction are allowed for this specific method by assigning enum as 'TransactionFlowOption.Allowed'  

[ServiceContract]

public interface IUserDetails

{

    [OperationContract]

    [TransactionFlow(TransactionFlowOption.Allowed)]

    public void DeleteUserData();   

    [OperationContract]

    [TransactionFlow(TransactionFlowOption.Allowed)]

    public void UpdateUserData();   

}

there are following option present in TransactionFlow attribute.
TransactionFlowOption.Allowed :Transaction can be flowed.
TransactionFlowOption.NotAllowed: Transaction should not be flowed. This is default.
TransactionFlowOption.Mandatory: Transaction must be flowed. 

Now implementing 'TransactionScopeRequired' attribute on specific method.

[OperationBehavior(TransactionScopeRequired = true)]
public void UpdateUserData()
{
  // database call goes here.
}

Once the scope assing, the last process will be enabling the transaction flow in config file.
 

Now consume the service by calling the UpdateUserData method and assign the scope block which check if the transaction method fails, if so then it will automatically rollback it.

using (TransactionScope Transcope = new TransactionScope())

{

  try

  {

   Services.UserDetailsService.UserDetailsServiceClient()

   clientVal = new Services.UserDetailsService.UserDetailsServiceClient();

   // code goes here to call method and assing the value.

   scope.Complete();

 }

catch (Exception ex)

{

scope.Dispose();

} 

}

I know this will helps to understand the concepts of transaction in WCF , if you have any query or suggestion please put your comments to know more.

 

Change schema name of tables, store procedure, views and functions

Today i come across one situation where i need to changes my current SQL schema to some other name. due to client requirement.so i searched few article and decided to write one article on same

Below query will returns list of all tables along with the schema name from your database.

SELECT TABLE_SCHEMA, TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES

If you want to add new schema you need to add that into sys.schemas table then only it will be accessible else it will give an error message as 

 Cannot alter the schema 'xxx', because it does not exist or you do not have permission.
 

IF (NOT EXISTS (SELECT * FROM sys.schemas WHERE name = 'Excprod'))
BEGIN
    EXEC ('CREATE SCHEMA [Excprod] AUTHORIZATION [dbo]')
END

You can also view list of schema from below query and you will find new schema "Excprod" get added.

SELECT * FROM sys.schemas

Now, below query used to alter the scheme tables

ALTER SCHEMA Excprod TRANSFER dbo.Temp1
ALTER SCHEMA Excprod TRANSFER dbo.Temp2
ALTER SCHEMA Excprod TRANSFER dbo.temp3

You may also alter the schema for store procedure as well. to find the list of all store procedures from your
database just use.

select * from information_schema.routines
where routine_type = 'PROCEDURE'

below query will generate the select statement for all list of sp

select 'ALTER SCHEMA Excprod TRANSFER ' + SPECIFIC_SCHEMA + '.' + ROUTINE_NAME
from INFORMATION_SCHEMA.ROUTINES where ROUTINE_TYPE='procedure'

Result will be :

ALTER SCHEMA Excprod TRANSFER synprod.Usp_Response
ALTER SCHEMA Excprod TRANSFER synprod.Usp_Request

To view list of view from database use this

SELECT * FROM information_schema.VIEWS

Please comment if you want more details on this.

Interview questions on WCF

Today i would like to share something about WCF, This is my first post on Windows Communication Foundation (WCF). since last 1 year i worked on WCF, so i would like to share my experience/points with you.

First will see what exactly mean by WCF . It's Microsoft programming model which helps for building service-oriented application. where we can send/ received the data asynchronously. service endpoint is the main channel where client can request data.

It has very good features :

1. Extensibility
2. Interoperability
3. Data Contracts
4. Security
5. Transactions
6. AJAX and REST Support

You may refer more about wcf here

 

 

Below interview question helps you to know more about WCF.

 

1.How session management worked in WCF?
answer - WCF manage the session by instanciating the service class. It basically used the Instance Context class to manage the server side at server side. you can refer more about Session management in WCF.

 

2. Is overloading possible in WCF? and How?
Yes method overloading is possbile in WCF. But yes it will raise the error as contract mismatch during method overload.
By providing the unique operationcontract name you can resolved that issue. It has Name property which expose the wcf method to schemas.

Look at the below example.
 

[ServiceContract]

public interface ICalculate

{

    [OperationContract(Name="ADD")]

    string methodName(int x,int y);

    

    [OperationContract(Name = "DISPLAY")]

    string methodName(string val1, string val2);

}

 

all the method get called by their attribute name and parameter value. 

for ex

ClientApp client = new ClientApp();

           

string method1 = client.methodName(1, 1);

string method2 = client.methodName("sample1", "sample2");

3.how to track no of visit to your service.
WCF has very good feature which enable us to manage the service call. with the help of this you can easily track the count. extension point is used.

4. list types of binding and have you worked on netMsmqBinding or netNamedPipeBinding ?

 

 

If you know more unique questions, please do share it.

creating word documents using open xml with asp.net

In my previous post i explained, how to prevent word file opening during the usage of Interop object using  C# and asp.net

Now in this article i will explain how to use the Office Open XML C# (alternate solution to the Interop object. 

The Open XML provides you set of .NET API. It helps helps you manipulate and creating the documents in the Open XML Formats
in both the environments (i.e client and server both) and that is without help of MS office applications.

Before using Open XML Format, you have to add the below namespaces in your C# class. Add references to the Packaging and Spreadsheet API components with the following code.

 

 

using DocumentFormat.OpenXml;
using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Wordprocessing;

 

Here is the CreateOpenXmlDocument function where you need to pass the filepath and it will created that doc file on specified positionl

 

public void CreateOpenXmlDocument(string filepath)
{
    
 using (WordprocessingDocument wordDocument = WordprocessingDocument.Create(filepath, WordprocessingDocumentType.Document))
  {
    // Add a main document part.
    MainDocumentPart mainPart = wordDocument.AddMainDocumentPart();

    mainPart.Document = new Document();
    Body body = mainPart.Document.AppendChild(new Body());
    Paragraph para = body.AppendChild(new Paragraph());
    Run run = para.AppendChild(new Run());
    run.AppendChild(new Text("Create text sample text, coding stuffs daily..."));
  }
}

Here now i am integrating that function into my page_load event.

protected void Page_Load(object sender, EventArgs e)
{

      string FilePath =  @"C:\\Temp";
      CreateWordprocessingDocument(FilePath);

      FileInfo myDoc = new FileInfo(FilePath);
      Response.Clear();
      Response.ContentType = "Application/msword";
      Response.AddHeader("content-disposition", "attachment;filename=" + myDoc.Name);
      Response.AddHeader("Content-Length", myDoc.Length.ToString());
      Response.ContentType = "application/octet-stream";
      Response.WriteFile(myDoc.FullName);
      Response.End();

}

 

 

This is just an sample doc creation , you may even format the document with adding images, graphs, style to para and may more. Just refer this Microsoft article on how to do this. 

feel free to raise your suggestion/comments on this. Thanks you and happy coding....

 

 

 

Microsoft.Office.Interop.Word how to prevent word file opening

In my previous post i explained, how to Convert the dataset to xml string using  C# and asp.net

Now in this article i will explain how to prevent the word file opening, i have bunch of word document and i want to read/search text value out of it.  i tried that using Microsoft.office.Interop.Word object. 

Here is the sample code which prevent the word to opening the main window.

private void PreventOpenWord(string Filepath)
{
 Application word = new Application();
 FileInfo fileInfo = (FileInfo)file;


object save = false;
object confirmConversion = false;
object visible = false;
object skipEncodingDialog = true;
object readOnly = true;
object filename = fileInfo.FullName;

word.Visible = false;

Document srcDoc = word.Documents.Open(ref Filepath, ref confirmConversion, ref readOnly, ref missing,
    ref missing, ref missing, ref missing, ref missing,
    ref missing, ref missing, ref missing, ref visible,
    ref missing, ref missing, ref skipEncodingDialog, ref missing);



foreach (Microsoft.Office.Interop.Word.Range docRange in doc.Words)
{
if (docRange.Text.Trim().Equals(textToFind,
StringComparison.CurrentCultureIgnoreCase))
{
  
IsWordFound = true;
break;
}
}
}
catch (Exception ex)
{
 Response.Write("Error while reading file : " + ex.Message);
}
}

Hope this will helps you.. Happy  coding.. 

Convert Dataset to xml string using C#

In my previous post i explained, Save images to database using SQL. Count string occurrence and much more articles realted with asp.net, SQL. Now in this article i will going to explain how to Convert the dataset to xml string using  C# and asp.net 

below is the short and sweet way to convert the dataset into xml.

DataSet dsUser = new DataSet();

SqlCommand cmdSelect = new SqlCommand("select name,age,location,ph,cell,status from userDetails ", conn);

SqlDataAdapter sda = new SqlDataAdapter(cmdSelect);

da.Fill(dsUser);

string strUserDetails = dsUser.GetXml();

Its very simple and easy method. Please post your comments for any suggestion.

Access content of iframe using jquery

It's very simple and straightforward.

Lets say, your using iframe and hello.aspx page like

1. < iframe id="frametemp" height="20px" width="90px"> </iframe>

which contain some control likes

2. <div id="divDisplayBox" > Say, Hello world! </div>

you can use .contents() method to find the specific id and like

3. $('#frametemp').contents().find('#divDisplayBox').html();

Hope this will helps you, Put your comments/suggestion if any.

 

Save images to database using SQL

Most of the time we want to save store/save images to database. In order to store image on sql server we need to store that in binary format. the most easiest way to do so in execute the SQL OPENROWSET command with SINGLE BLOB & BULK options.

Let's create one sample table and insert the sample result in it.

create table imageSave

(

   [img_name] varchar(250),
   [Img_binary] varbinary(max)

)

will insert some sample result into the imageSave table.

Insert into imageSave

SELECT 'SAMPLE Image', *

FROM OPENROWSET(BULK N'F:\Images\sample-test.jpg', SINGLE_BLOB) image;

Admin(sa) & developer has rights to work with OPENROWSET command.

Find Header & Footer template from Repeater control in .Net

This article will explain you how to find the Repeater Header and Footer template details.

I had created one user control which contain the Repeater. It generate the product showcase. i used that control in multiple pages but some where i need to update few details like header title , footer text at run time and that i have achieved it through find control.
Below example can helps you to understand the clear idea.

<asp:Repeater ID="ProductsDetails" runat="server">  
<HeaderTemplate> 
     <asp:Label ID="lblProductDetails" runat="server" Fore-Color= "Red"  Font-Bold = "true" />
 <br />  
</HeaderTemplate>  
<ItemTemplate>      
 Product Name : <%#Eval("Name") %> <br />  
</ItemTemplate>  
<FooterTemplate>      
 <asp:Label ID="lblPriceDetails" runat="server" Fore-Color= "Green" Font-Bold = "true" />  
</FooterTemplate>
</asp:Repeater>

Here i have define repeater control along with header & footer details , now i want to change the text of label called "lblProductDetails" at run-time. below snippets will helps you to get the Repeater details and base on that you can easily find the footer  & header controls  and change the text.


//Find HeaderTemplate
   Control TempHeaderDet = ProductsDetails.Controls[0].Controls[0];      
   Label lblHeaderDet = TempHeaderDet.FindControl("lblProductDetails") as Label;      
   lblHeaderDet.Text = "Product Description :";

//Find FooterTemplate

   Control FooterTemplateDet = ProductsDetails.Controls[ProductsDetails.Controls.Count - 1].Controls[0];            
   Label lblFooterDet = FooterTemplateDet.FindControl("lblPriceDetails") as Label;      
   lblFooter.Text = "Product Price:";


Yeap, i know its not very big deal... but yes some time this trick will helps you and save time as well. 

put your comments/ question in case of any concerns.

 

Andriod KitKat

Yes, once again andriod version has been named base on dessert.

after the cupcake, donut, Gingerbread, ice-cream sandwish and jelly beans. new decided name of next version of andriod as favourite chocolate "Kit Kat".

Android 4.4 KitKat

As andriod says people can easily remember such name because they can't leave without chocoates. :)

Here are the some versions of Android in Pictures

    Looks good, isn't it?   Post your comments and queries to know more about KitKat

C# zip unzip using window shell

If you want to zip / unzip files using C# code .yes its easy and you can do that without using any third party tools. using simple dll (Windows Shell32) you can do that quickly.

Just find below steps.

1.Create new project in Visual Basic 2010.
2.From the main menu, select Project -> Add Reference.
3.Select the COM tab and search for Microsoft Shell Controls and Automation.  

 

 Try using below code and zip/unzip your code.

Public Class Form1
 
    Sub Zip()
        '1) Lets create an empty Zip File .
        'The following data represents an empty zip file .

        Dim startBuffer() As Byte = {80, 75, 5, 6, 0, 0, 0, 0, 0, 0, 0, _
                                     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} 
        ' Data for an empty zip file .
        FileIO.FileSystem.WriteAllBytes("d:\empty.zip", startBuffer, False)
 
        'We have successfully made the empty zip file .

        '2) Use the Shell32 to zip your files .
        ' Declare new shell class
        Dim sc As New Shell32.Shell()
        'Declare the folder which contains the files you want to zip .
        Dim input As Shell32.Folder = sc.NameSpace("D:\neededFiles")
        'Declare  your created empty zip file as folder  .
        Dim output As Shell32.Folder = sc.NameSpace("D:\empty.zip")
        'Copy the files into the empty zip file using the CopyHere command .
        output.CopyHere(input.Items, 4)
 
    End Sub
 
    Sub UnZip()
        Dim sc As New Shell32.Shell()
        ''UPDATE !!
        'Create directory in which you will unzip your files .
        IO.Directory.CreateDirectory("D:\extractedFiles") 
        'Declare the folder where the files will be extracted
        Dim output As Shell32.Folder = sc.NameSpace("D:\extractedFiles")
        'Declare your input zip file as folder  .
        Dim input As Shell32.Folder = sc.NameSpace("d:\myzip.zip")
        'Extract the files from the zip file using the CopyHere command .
        output.CopyHere(input.Items, 4)
 
    End Sub
 
End Class