Rami Vemula

In this Demo, we see how to call a Wcf Service Method from JQuery. We make POST and GET Request for the same Service.

We have a ASP.Net MVC Webform, it only consists of html Controls. We have a simple Registration form, which takes User Name and User Email. Once We client the Submit Hyperlink, JQuery will make a POST request to the WCF Service, which will add the data to our Users List.

To retrieve the data, we have a simple Html Text Input, in which we fill the User Name. Once we give the input and click Retrieve Link, JQuery makes a GET Request to WCF Service, which searches the List of users and send back the Data to browser. We Display result in the Div tag.

The intended application got some secured products in the Sql DB (here the table is Products). Users can login to the DB and can only retrieve products thorough MVC Application. So User first needs to Register to the application, then he can login to the application to retrieves the secured information of the products.

The main attention of the complete process flow is “Registration”, especially Password field. Storing Password as a string into DB is considered as not a good practice, so first we generate a Password Salt using Cryptography, then we use the original Password String along with Password Salt to hash it into a more secured format using a Hashing algorithm. and finally it is stored in the Users table of Sql DB.

While Authenticating User, we get the Password String from User login, then check the DB for Username, get the User Entity from the DB, fetch the Password Salt associated with the User, Combine the Password string and Password Salt to generate the Password Hash, then finally cross check the generated Hash with that of the DB version. If both matches, Authenticate the user or else notify him as Invalid Login.

In the first part of this tutorial (PART I – Click Here), we uploaded files to the database in binary format using a FileUpload control. The plot behind saving files is to take the file from the FileUpload control, convert the same to the binary format, then save it to the DB. To make our accomplishment more flexible and maintainable, we use stored procedures along with custom classes for database transactions.

In this part of the tutorial, we retrieve the files (which are stored in a table of a database). For this purpose we first create a custom class which will hold the code for database transactions, then we create a generic handler which will process all the incoming requests for the downloading of files. Finally we create a web page which uses the before mentioned class and handler along with a repeater control to make the file available to the client.

In this tutorial, we first save files to the database in binary format, then in the second part of the tutorial we see how to provide a download option to the files residing in database. For uploading the files to DB, we use a FileUpload control and to provide download facility we make use of a Generic handler. The plot behind saving files is to take the file from the FileUpload control, convert the same to the binary format, then save it to the DB. To make our accomplishment more flexible and maintainable, we use stored procedures along with custom classes for database transactions. And the plot behind retrieving files is to use a handler which process the incoming request which are made to the files in database.

In this tutorial, we see how to develop a simple Contact Page webform. This Contact Page is going to be a similar one to what we usually see in our day to day experience out in internet. Here we use AJAX HTML editor to enable Html email to the owner of the website. The basic outline would be – Users provide their general details like name and email, and also they can provide Html Message (using AJAX HTML Editor) in the Contact Page, where a basic validation is done as first step. Then we take the Html string, and send the same in the email to the authorized person of the website (typically owner) using SMTP settings (System.Net.Mail namespace). For ease of use, we use Gmail SMTP settings (host and port) for sending email. For better interactivity UpdateProgress control is used to show the progress of email routine.

In this article, we see how to provide a download option (say for example to download images) to the users of our website. In accomplishing the requirement we use a Generic HttpHandler – which handles all the requests made for the download. For demonstration purpose we take some images and display them using a Datalist, in which we do provide an option to download. On download option click, the generic handler will process the request and displays an dialog in the client questioning client either to save or open the file, accordingly corresponding action will be taken place.

In this tutorial, we see how to develop a simple comments section. This comments section is going to be a similar one to what we usually see in our day to day experience. Here we use TinyMCE editor to enable Html Comments. And also catpcha is enabled (with the help of reCaptcha of Google). The basic outline would be – Users provide their general details like name and email, and also they can provide Html Comment (using TinyMCE), and finally they should enter the text showed in the captcha for validating robots. Then we take the Html string, encode it using HtmlEncode(), store it in database. Finally we retrieve the encoded string from the database, we then decode it and display it in the page as Comment.

In this part of the tutorial, we first create a Windows Service Project, then implement a Service called – ‘BirthdayEmailService’. Then we add a reference to our previously created Class Library – ‘EmailComponent’. We code BirthdayEmailService using Timer to perform the email sending task for every hour. Then we incorporate the Installer classes for the purpose of installation. Finally a Setup and Deployment Project is created for the Service. Finally the complete Solution is build and the exe file is generated which is ready enough to get installed.

In this tutorial, we learn how to send automated birthday wish emails to the customers of our product. We first design our database with basic details of every customer, and of course with a Email address field. Then we create a class library to hold the classes of database interactivity and to send email asynchronously. We use ADO.Net (for this tutorial I am skipping Entity Framework implementation, which usually I prefer to interact with Database. For generating EF modules of database, kindly watch this tutorial – Click Here) with a stored procedure for database interaction (primarily to fetch email ids of customers to whom we got to send birthday wishes). Then finally we use a Windows Service (which obviously run background in the server)through which the previously created class library is accessed and async emails are send.

In this tutorial, we first create a Database and store the necessary details of the Images like ImageName, ImagePath (physical directory path in relative URL), ImageDescription etc. Then we display these images on the web page using a Repeater in combination with SqlDataSource. After this we use Client CallBack to display the details of corresponding image on which mouse is hovered. CallBacks are accomplished by implementing ICallBackEventHandler.

1) In this tutorial (which is PART – II), we create a small website in ASP.Net 4.0 and we shall use a WebForm (named: PubsServiceTestPage.aspx) as a client to our service (which we created in former tutorial).
2) We Use the inline model of Webform (not the codebehind model).
3) We perform the actions using our client like, Getting all the Authors and display them in the Dropdownlist for selections, Selecting a Author and display his corresponding books using a Repeater, Modify and save the book details back to database etc.
4) To test the Client, we need the service to be running in the server, that can be simply manipulated by starting another instance of VS 2010 and running (Ctrl + F5) the PubsService.svc.cs.

1) In this tutorial we create a simple WCF service which is used to retrieve and save data from Pubs Database (Microsoft sample database).
2) The service also demos on how to use EF 4.0 and LINQ against database coding, with no requirement of writing SQL queries.
3) The continuation of this tutorial shows on how to create a client (say a WebForm in a website) to utilize this service.

  Hello Folks, This is the second section of my FIRST Video Presentation in IntStrings.com, Hope you guys enjoy it. The outline of the presentation – PART # 1 – Getting started with Entity Framework 4 in VS 2010. PART # 2 – Creating Model from existing Database (NorthWind Sample Database). PART # 3 – [...]

  Hello Folks, This is the starting section of my FIRST Video Presentation in IntStrings.com, Hope you guys enjoy it. The outline of the presentation – PART # 1 – Getting started with Entity Framework 4 in VS 2010. PART # 2 – Creating Model from existing Database (NorthWind Sample Database). PART # 3 – [...]

The present article demonstrates – “How to use LINQ Aggregate Query Operators”.

Aggregate Operators –

Max
Min
Sum
Count
LongCount
Average
Aggregate