The .NET Code Room

Parameter is not valid. Asp.net GDI exception

2011-06-12T23:49:00.001-07:00

I was getting this exception while working with the GDI images in asp.net.My requirement was to upload the image from client then resize it and display.The code was working fine on local development machine, but on production server it was throwing “Parameter is not valid” exception.The general cause of this is that non-availability of resources required to generate a valid image file.In my case

Generic function to display images on webpage asp.net

2011-06-12T23:47:00.000-07:00

Hi fellas,I am writing this post after a long time. This new year I am back at blogging to help the software developers in writing better code .Ever need of a generic/common function to display the images on website?In normal practice, whenever we need to show an image, we used to directly writeImage.Src= “/userfiles/abc.jpg”;This can be painful sometimes if your folder path gets changed, in

goDaddy hosting, send emails using asp.net

2010-05-23T00:28:00.000-07:00

I had very hard time in sending emails using asp.net on go daddy shared hosting.I tried many options like ssl, default credentials, smtp, ports etc.Finally below settings worked:1) Setting From Email (abc@domainHostedOnGoDaddy.com)2) SmtpClient as relay-hosting.secureserver.net3) Disabling the SSL4) Settings Credentials with username and passwordCode System.Net.Mail.MailMessage

Disable text selection and right click in html / asp.net pages

2010-02-10T01:38:00.000-08:00

If you want that your html page's content (text/images) should not be copied then you need to disable the right click and the text selection.Most of the scripts are available on internet to do this but most of them are not cross browser compatible.Disabling the right click works on all browsers, but the text selection blocking javascript code in mozilla prevents click on the textboxes. Means if

this._form is null or not an object, JavaScript Error

2009-10-04T01:58:00.001-07:00

I was getting below javascript error everytime i run my visual studio asp.net web pages:this._form is null or not an objectBecause of this error all my AJAX controls and page postback stopped working.As the error clearly states that it is a JavaScript error so i started checking all my Javascript code.Finally searching on the internet i found the cause and cure of this problem.Cause:If you are

Read Excel files using C-Sharp windows application

2009-06-24T02:49:00.000-07:00

This article explains how to read excel files using c sharp in windows applications.using System.Data.OleDb;private void btnRead_Click(object sender, EventArgs e) { try { string connStr = connStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Application.StartupPath + @"\Courier.xls;Extended Properties=ImportMixedTypes=Text;Excel 8.0;HDR=Yes;

URL rewriting using Global.asax, Error: The resource cannot be found.

2009-06-23T06:06:00.000-07:00

Today I implemented my first application having URL rewriting enabled.The application is created in Asp.net, C# and MS Sql 2005.The url rewriting logic was working on the my localhost but it didn't worked on production server.I was getting an error: The resource cannot be found. while accessing the newly created URL pages.I searched on Google about this and read lot, but nothing worked.Finally I

Traverse / Loop through all form controls in asp.net

2009-03-24T05:26:00.000-07:00

This post explains that how to traverse (loop through) all form controls in asp.net page.foreach (System.Web.UI.Control ctrl in this.form1.Controls){//here your code}Further if you want to get the state or data or manipulate the control, use the below code:Here I am checking that at least one DropDownList item is selected out of all DropDownLists in the current webform.bool isSelected = false;

Access your Asp.Net application over LAN

2009-01-09T05:07:00.000-08:00

This post explains how to access some Asp.Net Application residing on another machine on network.First of all you computer must be in the same workgroup as of the target computer. Then enter the following URL in the internet browser:http://192.168.1.84/myWebsiteTest/default.aspxorhttp://ajay/myWebsiteTest/default.aspxHere instead of ajay/192.168.1.84 you have to enter either the IP Address or the

MyBase in VB.Net is equal to base in C#

2009-01-09T04:39:00.001-08:00

The Mybase object of VB.Net is similar to the base in C#.So while using C# use "base" instead of "MyBase".Happy Programing.

Microsoft SQL Server DTS (Data Transformation Services) Import/Export Wizard Error

2008-11-15T04:44:00.000-08:00

If you are facing problems in “Choose a destination” option while importing and exporting data using Microsoft SQL Server DTS (Data Transformation Services) Import/Export Wizard, specifically the error mentioned below then this post may be helpful for you to get it solved.Error:DTS Import/Export ErrorError Source: Microsoft OLD DB Provider for SQL ServerError Description: [DBNETLIB][

Unable to validate data, ASP.net error

2008-11-06T22:59:00.000-08:00

Error:Unable to validate data, ASP.net error at System.Web.Configuration.MachineKeySection.GetDecodedData(Byte[] buf, Byte[] modifier, Int32 start, Int32 length, Int32& dataLength) at System.Web.UI.ObjectStateFormatter.Deserialize(String inputString)Information:This is an View state decoding error.Cause:The basic reason of this is the difference of key while encrypting and decrypting the

Username Regex Validation

2008-10-15T06:40:00.000-07:00

While accepting values from user you must validate the values because wrong values (like XSS attacks) can cause harm to your database and website.The validation can be done on server side and can also be done on client side.Here I am explaining server side as this is the most secure way.Althrough the client side validation is included in the source codeClick here to download visual studio

Read & Write to System Registry data, keys using C#

2008-10-10T06:07:00.000-07:00

In this post i am going to explain that how to access the System Registry and how to read and write data to registry. Step 1: First you need to import the below namespaces:using Microsoft.Win32; Step 2: Now create an object of Registry class:RegistryKey regkey; Step 3: Now access the registry and get the value of a key regkey = Registry.CurrentUser.CreateSubKey(@”Software\Microsoft\FTP”); if

Website Design Guidelines / Checklist

2008-10-06T05:39:00.000-07:00

1) Keep the raw file (e.g. psd, ai, cdr) in RGB format. Create the site design with the original dimensions (e.g. for 800x600=780, for 1024, 768=970).2) Try to keep text and images separate. Avoid overlapping of separate elements.3) Keep text content more than image.4) Always use web fonts like: Arial, Helvetica, Times New Roman, Courier New / Courier so that design at execution won’t look

How to get user’s IP address using asp.net

2008-10-03T04:01:00.001-07:00

Many times we need to get the current user’s / visitor’s IP address. Sometimes this is essential for security reasons.We must leg the user’s IP address in the following situations: 1) where you accept data from user, like guestbook newsletter, search page etc. This gives a plus point to the security of website, as you can get the user’s identity by his IP if he do something wrong with your

Preload images in HTML using JavaScript

2008-09-29T05:20:00.000-07:00

Preloading means loading an object (graphics, text, movie) before showing it to output. A good example is of preloading in flash files, when you see a loader before displaying the content, and after loading site shows a smooth experience of flow of data.This is mostly used when there is an mouser over images to be loaded. If user mouse overs an image and then you loads the new mouse-over

Using RequiredFieldValidator with DropdownList Asp.Net

2008-09-29T02:22:00.000-07:00

You may have used RequiredFieldValidator with Text controls, but if you wnat to use it with DropDownList controls, you need to do some little extra work. Here is the trick.Step 1: Create an DropDownListStep 2: Drag and RequiredFieldValidator. Set it’s ControlToValidate property to the DropDownLis’s object.Step 3: Fill some items in the DropDownList. Add a first item as “Select”. This will

Change MS SQL 2005 login password using sql query

2008-09-24T03:56:00.000-07:00

If you want to change the MS Sql 2005 ’s password then just run the following sql query after logging into query anlyzersp_password ‘oldPassword’ , newPassword’NoteAlways use strong SQL passwords (i.e. having uppercase characters , lowercase characters, numeric values, special characters) for security purpose, this way it will be difficult to hack, hard to guess, hard to crack by brute force

Show line breakes in Asp.net Label

2008-09-17T03:22:00.001-07:00

To show line breaks in a server side asp.net label, you can either use a HTML formatted text or a plain text.HTML formatted text contains “” tags so while rendering the control .net framework handles the task to show the proper html formatted text into a Label.Example:lblDescription.Text=”namedescription”;The above code will display a line gap between name and description.But in case if user

What is RSS feed

2008-09-12T00:34:00.000-07:00

Really Simple Syndication (RSS) feeds are XML files which are provided by websites so you can view their contents on other website rather than browsing their site. Basically it’s an information sharing process having some specifiedcontent format of text and related links.Example:I have a blog and you want to show the my Blog’s content on your website.So what i have to do is to create a RSS of my

Operator + cannot be applied to operands of type string and method group, C# error

2008-09-09T01:47:00.000-07:00

CauseThis error comes up when you tries to append two strings with the “+” sign. As the + sign in C# is a arithmetical operator so you cannot use this too append two string type values. To use “+” the values or variables must be if numeric type.As C# uses doesn’t supports implicit typecasting, for string concatenation use “&” sign.Examplestring varTest = "";string str1 = "abc";int str2=21;varTest

Send e-mail in ASp.Net 2.0 and onwards in C#

2008-09-06T03:27:00.001-07:00

The following code example can be used to send email using Asp.Net in 2.0 and higher versions version.The Namespace of email class is changed to System.Net.Mail from System.Web.Mail.Import the System.Net.Mail Namespaceusing System.Net.Mail;Code:MailMessage mail = new MailMessage();mail.From = new MailAddress(”info@yourDomain.com”,”Alert”);mail.To.Add(”you@yourdomain.com”);mail.Subject = “mail

Send e-mail using Asp.Net 1.1

2008-09-06T03:13:00.000-07:00

The following code example can be used to send email using Asp.Net in 1.1 version.First import Web.Mail namespace.using System.Web.Mail;Now add this code to your button click event:MailMessage mail = new MailMessage();String msgText = string.Empty;msgText = “Message here, you can also use Html tags for Rich Text Formatting.Hi.”;mail.To = “you@yourdomain.com”;mail.CC = “anyEmailAddress, its

Google’s Web Browser called Google Chrome is launched

2008-09-03T23:09:00.000-07:00

Yapee.Google has launched it’s own web browser named Google Chrome.Google Chrome is a very simple and sophisticated browser and very easy yo use.Google Chrome Features:~ Multiple tabs can be opened in same instance window.~ Thumbnails of most visited pages.~ Automatic bookmarks and history search reaults when you type any URL.~ Import settings and bookmarks from other web browsers.~ Application

Rename a table Column in MS SQL

2008-09-01T22:59:00.000-07:00

How to rename a MS SQL server database table column name after the table creation??You can rename a column regardless of it is null or contains any data.We need to use a System stored procedure to rename. Any command with alter keywords won’t work.CodeEXEC sp_rename ‘tableName.[oldColumnName]‘, ‘newColumnName’, ‘COLUMN’Example:EXEC sp_rename ‘Ultra_tblPressRelease.[uShowStatus]‘, ‘uShowInA2B’, ‘

ASp.Net 2.0 GridView Delete Button Confirmation pop-up

2008-08-30T03:22:00.000-07:00

While using GridView in asp.net pages wants to confirm the deletion form user. To do this we can take him to another page having GUI to confirm and then delete the record on that page.Instead of doing so much hardwork you can achieve this on the same page with a little bit of extra code.WorkaroundAdd a client alert script to the delete button of every row.In the delete event of GridView delete

Show Message Box in Asp.net

2008-08-25T03:27:00.000-07:00

It’s not possible to show an alert message box in asp.net using server side code (like vb.net windows apps, msgbox).But this can be achieved by generating a client side Java Script code in a server-side event.CodePrivate Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.ClickshowMsg(”hey there”, Me)End SubPublic Sub showMsg(ByVal sMsg As String, ByVal frm

Remove yellow autocomplete textbox background caused by Google Toolbar in Internet Explorer

2008-08-25T00:39:00.000-07:00

Hey guys,Recently i ran into this problem, some users of my client’s website complaint that in some web forms the name and email fields comes have a yellow background which hinders the readability of the field.After getting into depth details of the problem I came to knew that it happens only in Internet Explorer having Google Toolbar installed. In Firefox, Opera, Netscape it works fine.This is a

Update database data using SQL Cursors based on conditions

2008-08-22T00:27:00.000-07:00

Recently one of my MSSQL database got SQL Injection attacks.Hacker put some JavaScript code in all row data to get hits on his website (which is apparently blocked, and soon my site will also be got banned if it keep happening for a long time).Because the database has a huge amount of data, i can’t update table data using ExecuteNonQuery commands as it will result in a great overload on database

Change fore color of control using Java Script

2008-08-12T00:01:00.000-07:00

Many times we need to set the fore color or back color of controls (e.g. label, button etc).This can be achieved using CSS (supposing all of you know that) also but we can also do it using Java Script.This is a simple java script trick so you can use it with html controls as well as asp.net server controls.Here is an example for doing this :Code: