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Ultra-Rapid PHP Application Development

by Christoph Buenger

Describes PHP application development with the free Scavix Web Development Framework (Scavix-WDF).

Silent ClickOnce Installer for Winform & WPF in C# & VB

by Graeme_Grant

This article comprehensively covers the Microsoft ClickOnce Installer with a bare bones WinForm/WPF C#/VB Silent Updater framework plus covers how to implement, troubleshoot, test locally, to release.

On the fly Code Generation with Evolutility

by Evoluteur

A generic Web User Interface for CRUD applications generating all screens at run-time based on external metadata. It comes with sample applications for address book, memo pad, to do list, restaurants list, wine cellar, and database structure documentation that are easily customizable.

Remote File System Viewing and File Transfer using C# and TcpComm

by pdoxtader

Learn how to view a remote machine's file system using your own explorer like window, and transfer files and folders by dragging and dropping in C# using the TcpComm TCP library

Latest Articles

Silent ClickOnce Installer for Winform & WPF in C# & VB

by Graeme_Grant

This article comprehensively covers the Microsoft ClickOnce Installer with a bare bones WinForm/WPF C#/VB Silent Updater framework plus covers how to implement, troubleshoot, test locally, to release.

VB.NET/WinForms: Add MenuItem to SystemMenu

by vblover Programmer

Adding ContextMenu's MenuItem to the SystemMenu of Form in Windows Forms Application

Options for Database Backup and Restore - How to Export BACPAC using SSMS?

by Satya Karki

This article describes the options to restore and backup database in SQL Server and explains how to Export BACPAC from SQL Server Management Studio.

Azure Active Directory Authentication with OpenID Connect and Authorization with App Roles

by DotNetLead.com

Azure AD for authentication and authorization of users for your website

All Articles

Application

Interview Question

24 Jan 2010 by #realJSOP

They're asking you what experience you have with check-in/check-out systems. If you don't know what that is, then you have no experience with it.Like jimanuel said - tell them you don't know what it is, and see if they keep interviewing you.

Creating an application to take screenshots of windows in Windows Mobile using .NET 2008 and C#

4 Feb 2010 by #realJSOP

Maybe use google? I found this:http://www.dreamincode.net/forums/showtopic34831.htm[^]

How to convert C# mobile application to MFC

21 May 2010 by #realJSOP

Have you established that the device even has .Net on it?Oh yeah - smply saying "it didn't work" is completely useless when you're trying to get help from someone.

Trail period setup Process

2 Sep 2010 by #realJSOP

You're back. Use google to find a library that does what you want. there are literally dozens of ways to do this, certainly too many for us to list here.Like I said yesterday, it's a waste of time. Anything that can be done with software, can be UNDONE with software.

Os Version compatibility with .net frame work and sql server express 2005 installation

16 Sep 2010 by #realJSOP

Well, all of the software you're trying to install or use is compatible with SP2. Since there appears to be a problem, change your minimum requirement o includ XP/SP3 and you're golden.Anyone running XP should be running SP3 anyway.

SQL-Server-2005

Multilingual Application

27 Dec 2010 by #realJSOP

I used google to search for "make a web page multilingual", and this was the first of over 2.1 MILLION results returned:http://fci-h.blogspot.com/2008/02/how-to-create-malty-lingual-web-site.html[^]

About Mobile Application

27 Dec 2010 by #realJSOP

I don't know if you've heard, but there's this new thing available on the internet called a "search engine". The one that seems to be gathering the most use is something called "google". I know, it's a funny name, but from all reports, it seems to work.

Covert Windows based application to web interface

10 Jan 2011 by #realJSOP

I'd recommend Silverlight. It provides amuch richer experience that is desktop-like, yet delivered via the web. It works on any Windows box that has the approrpiate browser plug-in (most browsers). Debugging during development is also very easy.

Animated image does not work in ListView in windows application

15 Apr 2011 by #realJSOP

Try this CodeProject article:A Much Easier to Use ListView[^]

creating inventory application

20 Apr 2011 by #realJSOP

There used to be a Jobs forums on this site, but I can't seem to find it. You're gonna get hammered because of it.

how to hide border of Group box in .net application?

17 Jun 2011 by #realJSOP

Use a Panel container instead of a GroupBox (and this has nothing at all to do with the language you're using). Of course, you'll have to provide your own label to replace the groupboxlabel, but that's a small price to pay.

Tool for Business Application Development

7 Jul 2011 by #realJSOP

It's you. See the tool - BE the tool.The tool you're looking for is called a "programmer" (aka "developer").You can find a lot of them on monster.com.

how release my application for end user

7 Sep 2011 by #realJSOP

Is it a windows form app? ASP.Net? Something you pulled outa yer butt? You've given us NOTHING to help you.What does "still have problems" mean? EXACTLY What KIND of problems?

entity-framework

Resize image in windows appliation

19 Sep 2011 by #realJSOP

Why, with extension methods, of course:public static class ExtendBitmap{ public static Bitmap Resize(this Bitmap bmp, int nWidth, int nHeight ) { Bitmap result = new Bitmap(nWidth, nHeight); using(Graphics g = Graphics.FromImage((Image)result)) { ...

Storing images in C# Windows application

27 Dec 2011 by #realJSOP

I vote that you store them in the database. If you don't need transparency, I would use JPG because they can compress to a MUCH smaller size.

Timer control memory consumption

28 Feb 2012 by #realJSOP

Are you absolutely sure the Timer is the reason? Try using the debugger.

IPAD Apps that no sold in Apple app store

7 Mar 2012 by #realJSOP

I don't think an app can be installed without it being made available via the appropriate app store. I could be wrong, but that's what I remember hearing.

How to perform email verification

12 Mar 2012 by #realJSOP

The only way you can verify that an email address actually exists is to send a verification email to that email address that requires the user to click a verification link that will then update the database to indicate that the address has been validated by the user.

Set timeout for particular method of web service

13 Oct 2016 by #realJSOP

You can't set a timeout on a per-method basis, but could do something like what is described at this link:Crafting a Task.TimeoutAfter Method | Parallel Programming with .NET[^]My google search was "c# timeout with task".Here's some minimal code that may work for you:///...

000000 000000 0000000000

5 Nov 2016 by #realJSOP

This is not the place to go if you want someone to write code for you. I think I can safely say that nobody here works for free.This is a programmer's web site. I'm assuming that you think you're a programmer. If you can't come up with "any idea" on your own, maybe you should reevaluate your...

How do I search all the values or names in multiple columns in one textbox?

16 Mar 2021 by #realJSOP

0) Put the code into a try/catch block. try { con.Open(); SqlDataAdapter comm = new SqlDataAdapter("SearchMain", con); comm.SelectCommand.CommandType = CommandType.StoredProcedure; ...

How to host executable in windows service?

16 Mar 2014 by $*Developer - Vaibhav*$

Hi AllI have created one console application,having some ref dll.How to host executable (Console application exe) in windows service?Happy Holi.......... :)

how to integrate the winforms into one system

17 Nov 2014 by 123456789shaik

Hi, can any one tell me ,How to integrate the windows forms from on system to another system without loosing the dataplzzz help me...

enable and disable menustrip

25 May 2011 by 204.sharma

Sir, i have 2 window form(namely main_form and frm_login).In main_form i have a menustrip1 and want to enable and disable this on frm_login button ok.i declare the menustrip public but it doesn't work.how can i do this plz suggest.Thanks

get tweet from twitter

16 Nov 2011 by 204.sharma

Hiii, I need to get status from twitter in an C# console Application.At now time i am trying to do this by using twitterize framework dll.i got this from a site.but i unable to get tweet.i want to search tweet according to three query string.1.if i type #india then it must show all...

Converting Image Files to PDF without third party

22 Jun 2011 by 2irfanshaikh

I think below link will help youTutorials on creating PDF files using C# 2.0[^]

How to build language learning (web)applications?

16 May 2020 by 44voy44

There are quite a few applications out there, so generally it has been done and it should not be such a big deal since quite a few of these applications repeat the same features/solutions like ewa english app uses a similar suggest a translation...

Redirect to a page in the another project in same solution of a windows application in vb.net

17 Mar 2013 by 7774tlas

I had the same problem a few weeks back. If I recall correctly, there is no way to do this. I ended up just adding the form That I needed to the primary project. You CAN have the secondary form open when the primary form loads by right-clicking on the solution in the SolutionExplorer and...

How to display Video File Thumbnails in PictureBox?

18 Jun 2013 by 7774tlas

Hi, I would like to display a video thumbnail in a picturebox. I've been searching for answers, but most of what I've found (.GetThumbnailImage, System.Drawing.Image, etc.) seem to only work for images, not video. All I want to do is display the same thumbnail as windows file explorer. I have...

Simplest MVVM Tutorial -A Quick Refresher to WPF MVVM

13 Apr 2016 by @nkit Bajpai

This article discuss a simple application built using WPF MVVM design pattern and explain the basics of Command Binding and DataBinding.

I want to create a folder before the files generation

11 Dec 2017 by ________________

Using your principal, you can build any allowed filename: private string getfilename () { string dateWithSeconds = DateTime.Now.ToString("MM-dd-yyyy_HH-mm-ss"); string dateWithMinutes = DateTime.Now.ToString("MM-dd-yyyy_HH-mm"); string fullname...

Why Session_Start event in global.asax fires on each page request on my website.

28 Aug 2012 by _Amy

Session start event is fired only when a new session for a user starts. Once “Session_Start” for a user is fired then if the user makes subsequent request to any resource within the application this event is not at all triggered. The event is triggered only when the user’s session expires and...

how to get backup and restore

17 Jun 2013 by _Amy

Refer the links below:Backup and Restore SQL Server databases programmatically with SMO[^]Create Backups & Restoring Database In MSSQL [ASP.NET / C#][^]--Amit

Wait for some time and redirect to other page

6 Aug 2014 by _Amy

To do this, you need to have a program that runs in the background[^]. Try this:class Program{ [StructLayout(LayoutKind.Sequential)] struct LASTINPUTINFO { public static readonly int SizeOf = Marshal.SizeOf(typeof(LASTINPUTINFO)); ...

How to Make License for Windows Application

14 Jul 2015 by _Asif_

This is not going to be an easy task for you. It would be better if you get a library that do the job for you. This article Licensing systems in .NET[^] seems a good starting point

SQL-Server-2008R2

how to export grid view to pdf,excel,word documents..desktop apllicatio

11 Feb 2013 by _Dhull

how to export grid view to pdf,excel,word documents...desktop apllication.help ASAP please

What is the best method for converting a dekstop app to a web app in another language

19 Nov 2013 by _Maxxx_

I don't know xojo.However, if it is a simple app, you already have some xojo skills, and xojo seems that it will enable you to have both the desktop and web app with a common code base, then I would stick with that.Developing in PHP or ASP.NET or whatever else would seem to me to require...

Print Images on Crystal Report Through Database

26 Dec 2012 by _Vitor Garcia_

Vague question, short answer :Select that field from Table then put that field into your Report. that should do.

how to validatate (restrict string )allow number followed by upto four decimal by regular expression in c# web application

13 Apr 2011 by a1mimo

you know what I dont really have that experience in regular expression but here is an answer that might help youput this before the eventstatic int afterdot=0;static bool dot=false;at text changed event put this codefor(int i=0;i{ ...

What are ways a winforms application project created be used, adding specialized features as another project

16 Apr 2018 by Aa20

I already have a generic winforms application project but i want to create a special case project adding specialized features on top of the old one and at the same time, i want all enhancements/versioning done on the old project to be used by the new project. I still want the develop and improve...

Regarding DatagridView Vertical Scrollbar

20 May 2014 by aamitsengar

Look at Properties of Gridview Scrollbars = Vertical/Both/ Horizontal

How to call multiple form in Mainform in particular area without changing Mainform Layout

20 May 2014 by aamitsengar

actually What u want ?Want morethen 1 form in mdi parent form ?then Create a class and then use Get set for Form name if instance of that form is not available then open new form otherwise return Current Window

please can any one help me to this task "selected items in checkedlistbox display in to textbox c# windows application"

20 May 2014 by aamitsengar

how can you declare thisint i = checkedListBox1.SelectedItems.Count;for (i = 1; i >= 3; i++)Look at 'i'choose different variable

how i do get a value of variable in form2

11 Aug 2012 by Aarti Meswania

pass controls/variables while create instance of new formeg.public class formDest{ public formDest(string c) { //something to do }}now, pass value from source form to destination formpublic class formSource{ public void btn_click(...) { formDest fd = new...

Allow enter space in text in two strings and first first space is not allow

28 Aug 2012 by Aarti Meswania

In textbox's keypress event put this condition,if (e.KeyChar == " " && c.Text.Length==0)//for block first whitespace { e.Handled = True;}if (IsNumeric(e.Keychar))//for block numbers { e.Handled = True;}IsNumeric function...public static Boolean IsNumeric(string...

How can I make Hover effects to windows desktop application using vb.net

5 Nov 2012 by Aarti Meswania

No, CSS RequiredWindows Application Controls Provides lots of eventsCreate Two event of your control1. Mouse enter2. Mouse LeaveNow, For example in mouse enter eventYourControl.BackColor = Color.Greenin Mouse Leave eventYourControl.BackColor = Color.TransperentHappy...

Using the TAB ORDER with ENTER KEY ?

20 May 2013 by Aarti Meswania

use Sendkeys.send methodTips: add all textboxes' & controls' Keypress event you want to work as tab on enter key press.. see underline portionprivate sub textBox1_KeyPress(object sender, KeyPressEventArgs e) Handles textbox1.keypress, textbox2.keypress... if (e.KeyChar == 13)...

How can i publish windows application with crystal report ?

3 Jun 2013 by Aarti Meswania

1. you should pack report file (.rpt file) with setup2. set path varible (using reflection) not using application.executepathHappy Coding!:)

Matrix in Java (GUI)

17 Jan 2014 by Abdelrahman Elzedy, Abeer Touny

A description for a Java code implementing a Matrix program in a GUI form

How to Convert byte array to ImageSource for Windows 8.0 store application

26 Feb 2014 by Abdul Muneeb Abbasi

I am working on Windows 8 store application. I am new at it.I am receiving an image in the form of byte array (byte []).I have to convert this back to Image and display it in Image Control.so far I have button and Image control on Screen. When I click button, I call following...

How do I highlight specific area in Windows Phone 8.1 map control?

6 Mar 2014 by Abdul Muneeb Abbasi

HiI want to highlight area in a map, it can be any area (irregular shape). Any suggestions, how can I achieve this using1. Windows Phone 8.1 map control2. Any third party maps I can do pushpins in map control, but I have to highlight area.Help is much appreciated?Regards

Windows-Phone-8

ASP.NET Single Page Application (SPA)

31 Jul 2013 by Abdul Q

Hi,I am new to ASP.NET Single Page Application (SPA) using Backbone.js and Marionette.jsCan anybody provide a solid code example with explanation to get started with Visual Studio 2012Actually, I need a working example in VS2012 using ASP.NET SPA(MVC4) + Backbone.js and Marionette.js...

C#.net WinBase Connection String management

17 Nov 2010 by Abdul Quader Mamun

You can write user input as connectionString in XML file. Or in Write to web.congfig file. http://www.codeproject.com/KB/cs/readwritexmlini.aspx[^]http://geekswithblogs.net/akraus1/articles/64871[^]May help you.Thanks

Evaluate paragraph line spacing in word using word interop C#

2 May 2017 by abdul subhan mohammed

Dear All, We are automating MsOffice in our winForm application(C#). Where I have create one method to "Evaluate the paragraph line spacing". In the word document, there will be paragraphs and this method will find the line spacing from the specific paragraph. I have set the paragraph line...

Office-Automation

Unable to close powerpoint application using office interop C#

9 May 2017 by abdul subhan mohammed

Dear All, We are automating MsOffice in winform application(C#). Currently we are working on, to create a powerpoint file(Programmatically). We are successfully created pptx file. After creating a pptx file, we are trying to close both the presentation and application. Its clsoing only...

Office-Automation

Axwindowsmediaplayer not displaying the video in winforms programmatically C#

20 Feb 2019 by abdul subhan mohammed

Dear All, I have one windows application where I want to play audio/videos files. First of all, I have added the reference to the WindowsMediaPlay in Com tab in my project solution. I have then added this as the tool by right-clicking in the menu tool and selected the WindowsMediaPlayer. What...

Can't write anything while the timer is running in C#

4 Feb 2018 by abdul wadood

I have made a timer which runs backwards starting from 10.I just wanna create a little simple game.I wanna write the sentence 'I love programming' under 10 seconds if i am able to do it the message should shown 'You win , gratz' but when the clock runs out of time the message should be shown...

Attributes and FileSystemAccessRule in metro app

28 May 2013 by Abdullah Mughal

1. I am suffering a problem that I didn't find hidden attribute in metro app, is the keywords are changed in metro app.2. and my second question is related to FileSystemAccessRule. I also didn't find FileSystemAccessRule as present in vs2010. Kindly help needed!

WPF: How to make a Drawing Application?

20 Jan 2013 by Abed AlSayed

Hi, I want to make a Paint like App(pencil, text, eraser, lines & shapes drawings) with ability to resize shapes & edit Text at any time (Like Microsoft PowerPoint) in WPF.My Question is : What Tools should I use? (for some reasons I don't want to use Inkcanvas)And how to make my own...

Configure same server with different port on ARR

6 Jul 2016 by Abhijit Parab

I have 2 App servers where I have hosted two websites. both applications are running on different port.Now I want to configure ARR server which will route request to these two APP servers. How can I configure APP servers on ARR with different Port in same server Farm ?For example...

How to import data from access database to sql server 2008 using C#

30 Dec 2012 by Abhimanyu Rawat

HelloI want to import data from access database to sql server 2008 using c#.With some validation means,In Access we have varchar(10) and sql we have varchar(11) then not allow to import data. like vise if name is not match of the column than also not allow to import.Thanks

how to close application after 3 wrong login tries in windows form application

26 Feb 2013 by Abhimanyu Rawat

Helloyou just take one integer variable for e.g. int count=0every wrong attempt just increase the variable value like count++if(count >3){ Application.Exit();}Happy CodingThanksAbhimanyu

how to generate keypress even?

13 May 2014 by Abhinav Chaudhary

private void textBox4_KeyPress(object sender, KeyPressEventArgs e){ int ascii = Convert.ToInt16(e.KeyChar); if ((ascii >= 97 && ascii = 65 && ascii

Comparing the sound in 2 wav files?

21 Feb 2010 by Abhinav S

This[^] article suggests a Compare() method that could be used. Check if this will meet your requirements.

ASP.net 3 tier web application in LINQ to SQL

2 Apr 2010 by Abhinav S

See here for a sample.

User Control dynamic Control to be Bring to front of other Parent Control

19 May 2010 by Abhinav S

Try setting the zindex of the dynamic control.Search on msdn to read / learn more about this property.

16 Jun 2010 by Abhinav S

This article has a lot of information on SQL Injection - it does not talk about detection but may actually give you some ideas.

ASP.net chat application

5 Jul 2010 by Abhinav S

Please provide a link to the article you are talking about or better still, post a message in the messages section below the article.

Start a file in application

25 Jul 2010 by Abhinav S

See if this[^] helps.

Deploy VB.NET Applications

6 Aug 2010 by Abhinav S

This[^] may help.

How to make a file open in another application C#

26 Oct 2010 by Abhinav S

Create a new C# process object (for this see here[^]).Then use the command line parameters given here[^] to open the file.You will probably need the command line vlc [file://]filename.

.NET Application Error

20 Jan 2011 by Abhinav S

Make sure the correct .Net framework is installed on your notebook.

asp.net and arabic language. How to change the layout when language switches

9 Feb 2011 by Abhinav S

As you can see here[^] .Net 3.0 and above have bidirectional support. Thus if you are using 3.0 or above, you should be ok.

C# Windows Application + SQL Server 2005 express

11 Feb 2011 by Abhinav S

If you are using ODBC settings, check that these have been configured properly.

can we use validation for floating numbers in a dynamically text box C# web application

7 Apr 2011 by Abhinav S

Yes we can.Add an event handler to the dynamic textbox and implement your validations in the handler.

how to make a form readonly in c# web application

19 Apr 2011 by Abhinav S

This [^] should surely help you out.

font problem in printing in c# web application

25 Apr 2011 by Abhinav S

The browser settings may be overriding your applications font settings.

date time picker problem

27 Jul 2011 by Abhinav S

Try dateTimePicker1.value = new DateTime(DateTime.Now.Year, 12, 31);

how to display image field in microsoft report in vb application?

6 Aug 2011 by Abhinav S

Have a look at this[^].This[^] might be able to help you out as well.

Is there any advantage of using multiple DB in one application ?

13 Sep 2011 by Abhinav S

If you can write your code generic enough to replace one db with another, then this would add to the sale value of the application. One client can use, say, MySQL while another client can use SQL Server with the same application.However, do this only when you think it is worth the effort....

girdeview problem help me friends

1 Oct 2011 by Abhinav S

See http://msdn.microsoft.com/en-us/library/system.windows.forms.datagridviewcomboboxcolumn.aspx[^] for adding a drop down.

Create Connection String Window Application

31 Oct 2011 by Abhinav S

For connection strings have a look at http://www.connectionstring.com.Just for your information, there is no thing like framework 3.2.Either there is framework 2.0 or framework 3.0.

how to convert .doc file to .pdf file

30 Nov 2011 by Abhinav S

You can use iTextSharp to do this - here is an article on how to do this[^].

Asp.net with C#.net

1 Feb 2012 by Abhinav S

ServerVariable...

How to Bind ComboBox in DataGridview Using windows application

24 Feb 2012 by Abhinav S

Have a look at the DataGridViewComboBoxColumn class[^]. Cascading dropdowns might help you create a selection where you can choose country, state and city.

I've a bit problem with my coding. What i m trying to do is to add a row in a table, but i m having errors. Any idea Pls help me

27 Feb 2012 by Abhinav S

You are trying to access a member of an object that is null or not set.Read more about this error here[^].

using dynamic label using C#

16 Mar 2012 by Abhinav S

Trypublic void AddMyControls() { TextBox textBox1 = new TextBox(); Label label1 = new Label(); // Initialize the controls and their bounds. label1.Text = "Text label1.Location = new Point(48,48); label1.Size = new Size (104, 16); // Add the Label control...

Dispaly modem name in combobox

18 Mar 2012 by Abhinav S

Take a look here[^].This is C# but you should be able to convert the code to VB.Net.

c#.net need to resolve "System.InvalidCastException" when we using LINQ

9 Jul 2012 by Abhinav S

Try vGroups.AsEnumerable().Distinct()

how to design a multilingual application

20 Jul 2012 by Abhinav S

When you design a multi-lingual application, you need to look at two aspects, Localization and Globalization.To read more about globalization, try http://msdn.microsoft.com/en-us/library/9xdxwwkc%28v=vs.80%29.aspx[^].For localization (and design), have a go at...

How to create effective Multithreaded window application ?

12 Sep 2012 by Abhinav S

TryThe key to multi-threaded Windows Forms UI interaction[^]http://msdn.microsoft.com/en-us/library/ms951089.aspx[^]http://msdn.microsoft.com/en-us/library/ms229730.aspx[^]If you want to use the application over the internet, think of using ASP.Net rather than Windows Forms.

Windows 8 app idea

28 Sep 2013 by Abhinav S

It depends on who is holding this contest and in which location.You should go through terms and conditions before proceeding further with this idea.

What is the best method for converting a dekstop app to a web app in another language

19 Nov 2013 by Abhinav S

I guess rewriting a VB6 program in any web based language would take more or less the same time.It depends on what the team is more conversant in.One thing you could check is if the same SQL queries can be utilized in both cases.It could reduce some amount of effort.

Extract data from exe program to c#

17 Feb 2014 by Abhinav S

You can use a tool like ISLDAM [^] to view code of the program.

How to host executable in windows service?

17 Mar 2014 by Abhinav S

You cannot host a windows executable in a windows service.Convert the application to a service.

How to convert english to gujarati,hindi using windows form application c# offline.?

9 Aug 2014 by Abhinav S

You will have to build your own conversion language parser or buy a third party one and use it (or a trial version) in your own program.There is no other way.

How to exit a loop in c# windows application

5 Jan 2015 by Abhinav S

You have to use the background worker class - http://stuff.seans.com/2009/05/21/net-basics-do-work-in-background-thread-to-keep-gui-responsive/[^].

How to display a table in column name in date wise

31 Aug 2015 by Abhinav S

A Pivot should do - PIVOT[^].

for loop or for each or while using display a DataGridView

17 Sep 2015 by Abhinav S

You know you have to get the top 10 rows. Use id and achieve this in one line -select Name from table_name where id

How we will know if a user is already logged in to his account from some other place?

20 Sep 2015 by Abhinav S

You have to build logic in your application to handle this scenario.Simplest solution is track each login (with the time) in a database.If the user logins from any other location check this table and display a message.You will need a clean up job to empty this table after some time.