.NET Tutorials, Forums, Interview Questions And Answers
Welcome :Guest
Sign In
Win Surprise Gifts!!!

Top 5 Contributors of the Month
Gaurav Pal
Post New Web Links

Question about Greater/Less Than if Value is Null

Posted By:      Posted Date: August 24, 2010    Points: 0   Category :ASP.Net

Currently on my site I am displaying wins and loses based on the score of an event. I got this to work except when both of the values are null. Until an event happens the values are null so when I am trying to show a greater than or less than statement that is grabbing a null value I get an error because it's not in the correct format. I also checked out this article here: http://www.codeproject.com/KB/cs/AgileWare_Convert_Int32.aspx

This code is within a DotNetNuke module right now and crashes because of this format. So basically I am looking to modify my statements below in some way where if the value is null it will still display on our site. Obviously if the values both show 0-0 it works but that isn't really an option for me to use prior to the event happening. Any help is appreciated. Thanks!

I've tried both Convert.ToInt32:

  if (objAwaySchool != null)
                    string strSchoolId

View Complete Post

More Related Resource Links

Some basic MVC question

  1. In regular asp net I can run (debug) the application but I can either "view in browser" that gives me the option to view the application and write code on same time.

In MVC I can't find this option.

  1. What is the basic DATA MODEL for working with SQL DB.

I mean with no any framework (entity framework, Sub sonic, Link to SQL etc')

I look for basic application that works with data but with no fw.

  1. What is the popular DB framework that working with data.
  2.  I am looking on  mvc series


C# Soup To Nuts  (the best series ever)


I watch some of the MVC video, seems that the music store is good but I have to wait to the other part.

Does any one know and recommend   a Microsoft MVC tutorial?





Web Site to Web Application Question


I've been building web sites and for my next project I will be creating a web application.  I use a 'BasePage' class in all my projects but, since web applications do not contain the 'App_Code' folder, what is the best place/practice for the 'BasePage' class?



How to check for null/empty strings on dynamic objects?


What is the proper way to check for null or empty strings on dynamic objects? This is the only solution I've found so far:

if (admin.PasswordHash.GetType() == typeof(DBNull) || admin.PasswordHash == string.Empty)

If the field is null, the object returned is DBNull.Value, but if the field is empty string, it's return as a System.String object. This makes it impossible to do regular "admin.PasswordHash == DBNull.Value" check, as that will fail whenever the field has been set to empty string. Is my example the right (and only) way to go?

connection string question from a newbie


when publishing  in the webmatrix dialogue it asks for "destination connection string" for my "database.mdf"

I was not sure what it was so I pasted this from my web.config file :

Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\database.mdf;Integrated Security=True;User Instance=True

it all published ok, but wont run, so I guess it has somthing to do with this connection string or some kind of configuration issue.

My question is this, What should go in the field for "Destination connection string"

Security Question Answer Retrieval


I know there is a method built in for retrieving the encrypted password, but how do I retrieve the encrypted security answer?

What I want to do is have a member profile update screen that the end user can update their password and security question and answer. However, when they get to this page, I want to already be showing the security question (the easy part) and its answer (the not so easy part).

I have updated web.config with passwordFormat=Encrypted and have added a machineKey with the generator (forgot the link, but located on eggheadcafe somewhere).

I haven't done ANYTHING yet, since I already have a user store with hashed information. I wanted to get some functionality done before publishing, wiping the store and recreating users (only a couple developers).


Users getting logged out because HttpContext.Current is null


We've  been trying to fix this one for a couple years, and I'm just out of ideas, so any help is really appreciated!

We've got a fairly large, complex web application that uses Forms Authentication to authenticate users.  Throughout the application we store and retrieve information about users in the Session object, and in some cases in cookies.  In a couple places we check for the existence of the context, and if it's null we send the user back to the login page to re-establish the session. 

Just a quick run-down of this web app: C#, .NET 3.5, IIS 6, ASP.NET State Service to manage session

As for the session timer, we use our own home-grown timer, which is basically a client-side timer, which is backed up by a check to the SQL database to see when their last activity was.  This seems to work well for us.  It's not perfect, but it allows us to notify the user before the session times out, and allows us to be certain we're not logging a user out before their 60 minutes of inactivity is up.

What's happening is that certain users are being logged out after just a few minutes.  We've eliminated the timer as a cause and believe what's happening is the HttpContext.Current is null, so the user is logged out.  We do not know why the HttpContext.Current is null, and I underst

Very Basic Question - Error message running first page


Hi Everyone,

I am running Windows 7 and I have gone into Control Panel and activated all of the IIS Functions.

The web application I am running was downloaded from the net (and has worked on other machines previously).  Once I downloaded it, I moved it into C:/inetpub/wwwroot/code/main.asp

I am a bit of a novice at this!  But I am hoping someone can point me in the right direction!


I get the following error when I try and run the web application through IE:

"An error occurred on the server when processing the URL. Please contact the system administrator. If you are the system administrator please click here to find out more about this error."

(When i click the "click here" button it just goes to the IIS site).


Appreciate any help I can get!




C#, LINQ: (List<>) Question???


Hi Everyone,

I have a strange problem:


There is an entity (Table) called "Filters" in my .edmx which has all my tables and stuff in it (to use it for LINQ queries)

I have created a class called "CustomFilters" which inherits "Filters". So now my cutom class has all the properties of the original "Filters" class (table) and 1 more additional property that i wanted which is a List of "CustomFilters":

List<CustomFilters> children = new List<CustomFilters>();

Now i get all my records into:

List<CustomFilters> theOriginalList = new List<CustomFilters>();

NOTE: first all records are tken into a List<Filters> and then these are added into List<CustomFilters> where List<CustomFilters> for children of that record is added, and then children of the child records, and so on......

so now, every record is an instance of CustomFilters which has a property named "children" which is a list again; and each child again has instanaces of "CustomFilters", and each instance again has children...and on and on and on.....

(basiacally its a data source for a treeview in my silverlight control)

every thing is good and working as expected.


linqdatasource parameters question



I'm currently getting to know the linqdatasource control. What would happen if several WHERE parameters are added to the linqdatasource control declaritively in the aspx page but no WHERE clause is defined? 

1. is there any issue with setting up multiple WHERE parameters in the aspx markup for linqdatasource but then deciding which ones actually get used at runtime by setting the actual WHERE clause at run time? Would the unused parameters simply be ignored and cause no issues?

2. when you need to modify WHERE clause or WHERE parameters at runtime do you need to do so in an event handler? such as linqdatasource.selecting?
I see from the above link it is possible, but is that the standard way to handle controlling filtering in code behind for linqdatasource?

2b. if you use an event such as linqdatasource.selecting to add where parameters and/or modify the where clause in code will that also break the builtin sorting and paging support of the linqdatasource with a gridview? 

database interface design question


For handy database interface, is it good to use SqldataSources exclusively intead of EntLib functions?

Thanks for any feedback.

A Challenging Question for Advanced user....


Using  dot net How will you release .exe applicattion for 1000 clients.this question was asked by manager but i could not answer him.tell me if you can!!!

Question in Get method in C#


I got a recent working code from client.I see errors in the get methods when i compile , below are some place where the error happens.Can any one help me out?


Error 2 'System.Environment.NewLine.get': cannot explicitly call operator or accessor C:\Documents and Settings\shankar\My Documents\Visual Studio 2008\Projects\DKCLwin\DKCLwin\LocalizationAdmin.cs 150 170 DKCLwin

Error 2 'System.Environment.NewLine.get': cannot explicitly call operator or accessor C:\Documents and Settings\shankar\My Documents\Visual Studio 2008\Projects\DKCLwin\DKCLwin\LocalizationAdmin.cs 150 170

'element.className' is null or not an object



I just downloaded the project, compiled it and ran it right out of the box and when I put the mouse pointer over or remove the mouse pointer from either MenuItem in the menu demo, I generate this error:

'element.className' is null or not an object

It points to this javascript method:

updateClassName: function(operation, element, name, value) {
        this[operation + 'String'](
                function() {
                    return element.className;
                function(newValue) {
                    element.className = newValue;

Silly sintax question


I'm just discovering MVC with Visual 2010 using MS Training kit.

Can somebody explain me why we can always seefor the index view

<h2><%=ViewData["Message"] %></h2>

And the code generated by visual studio

<h2><%: ViewData["Message"] %></h2>

Is there any difference between %= and %: with any document on that



Page.FindControl Causing Null Reference Exception


Hi guys,

I developed a page in VWD 2008 and it works perfectly locally, but when I deployed it on the server every Page.FindControl() call is causing the NullReference Exception "Object reference not set to an instance of an object. " Can anyone help me out? Code is below


Mike Marshall

            For i As Integer = 1 To 10
                If (CType(Page.FindControl("last_" & i), TextBox).Text.Length > 0) Or (CType(Page.FindControl("first_" & i), TextBox).Text.Length > 0) Or (CType(Page.FindControl("dob_" & i), TextBox).Text.Length > 0) Then
                    Dim person_entry(7) As String
                    person_entry(0) = info_list.Count - 1
                    person_entry(1) = CType(Page.FindControl("last_" & i), TextBox).Text
                    person_entry(2) = CType(Page.FindControl("first_" & i), TextBox).Text
                    person_entry(3) = CType(Page.FindControl("dob_" & i), TextBox).Text
                    person_entry(4) = CType(Page.FindControl("appear_" & i), TextBox).Text
                    person_entry(5) = CType(Page.FindControl("mental_" & i), TextBox).Text
                    person_entry(6) = CType(Page.FindControl("behave_" & i), TextB
ASP.NetWindows Application  .NET Framework  C#  VB.Net  ADO.Net  
Sql Server  SharePoint  Silverlight  Others  All   

Hall of Fame    Twitter   Terms of Service    Privacy Policy    Contact Us    Archives   Tell A Friend