ASP.NET PRO readers choice awards

You can vote for ASP.NET readers choice awards here:

http://www.aspnetpro.com/awards/default.asp

give a hand to your favorite components, controls, utilities, editors and so on!

Nice UML Diagram

Here is a very nice and informative UML diagram I created while I was bored ;)






Just kidding :)

Removing the left "placeholders" in telerik radMenu (where the images should be)

I needed to remove this placeholder as our menu was without icons. First I thought it is impossible, but then I found very helpful thread in telerik forums.
It says you need to apply the following CSS to your form:

.RadMenu_[SkinName] .rmGroup .rmLink
{  
   padding-left: 0px !important;  
}  
    
.RadMenu_[SkinName] .rmGroup .rmLink .rmText
{
   padding-left: 5px !important;  
}  
.RadMenu_[SkinName] .rmGroup
{
   border: 1px solid #979797 !important;  
   background: #f0f0f0 !important;
}

Where [SkinName] stands for the skin of the menu.


By the way - it happens this to be my post #100! ;). Hope I helped someone with all my posts :).

Read various elements from the connection string.

I saw a question in ASP.NET forums. There was a guy asking how to extract the Username and Password from a connection string, stored in the web.config.

I recalled doing something like this but was not able to recall which class I used.

After about a day another guy posted an answer on this question - the class was SqlConnectionStringBuilder. You can use this class to easilly manage SqlConnection string properties such as DataSource, Username, Password etc.

Here is my post on how to get a connection string from the web.config:
Read connection string from web.config

Here is some more info about SqlConnectionStringBuilder from MSDN:
SqlConnectionStringBuilder class

Combining both resources will help you manage your connection strings easilly.

Read the connection string from the web.config file

Here is this code, it is replicated bilions of time in Internet, yet I fill obliged to paste it here...

This is the first way, which I took from Microsoft.
It checks if there is a connection strings section, then it checks if the count of connection strings is more than zero:

        System.Configuration.Configuration rootWebConfig = System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration("/MyWebSiteRoot");
        System.Configuration.ConnectionStringSettings connString;
        if (0 < rootWebConfig.ConnectionStrings.ConnectionStrings.Count)
        {
           connString =
             rootWebConfig.ConnectionStrings.ConnectionStrings["MyConnectionString"];
           if (null != connString)
           {
             // Do something with the string, for example - create SqlConnection object:
             SqlConnection con = new SqlConnection(rootWebConfig.ConnectionStrings.ConnectionStrings["MyConnectionString"].ConnectionString);
           }
        }


This one is the short line (no checks if anything fails, after all if you don't have a connection string in 99% of the scenarios you will want to have exception rised).

string cString = System.Web.Configuration.WebConfigurationManager.ConnectionStrings["mine"].ConnectionString;

Fixing sup - sub for radEditor example

I made few posts on telerik radEdit. There was something I considered a small issue. Which actually may appear not to be issue, but to me it was.
So i decided to get a bit more familiar with the telerik radEdit client side scripting API (thanks to Tervel for his valuable comments).
So the problem for me was that if you type normal text, then click on the sub icon to make index and then click on the sup to raise to the power of something, the result was a text on the same level as the normal text.

Digging a bit in the client API of radEdit I found that you can obtain the editor undo manager. You can also fire commands so the problem should be easy to fix (I should mention here that I am really happy with the architecture of radEditor, it has everything a developer may need in order to extend the control to fit his / her needs.

Ok, now to the problem. I thought all I need to do is to make radEdit check if a sup is selected when you click sub and switch it off if so. Same thing should happen for sub. Luckily radEdit has client side event handler OnClientCommandExecuting which is rised prior command execution. So you will need an event handler like this:

OnClientCommandExecuting="cmdPreExec"

Having the eventhandler attached, you need to write a function to check if the user clicks either sup or sub. Then to check if the other command was recently fired, if so - it will fire it again to switch it off. Here are the functions:

     function cmdPreExec(editor, args) {
        var strCommand = getLastCommandReal(editor);
        if (strCommand) {
           cmd = args.get_commandName();
           if (cmd == "Superscript") {
             if (strCommand == "Subscript") {
                editor.fire("Subscript");
             }
           }
           if (cmd == "Subscript") {
             if (strCommand == "Superscript") {
                editor.fire("Superscript");
             }
           }
        }
     }

     function getLastCommandReal(editor) {
        var manager = editor.get_commandsManager();
        var commands = manager.get_commands();
        var lastCommand = null;
        
        if (!commands) {
           return null;
        }
        else {
           for (i = commands.length - 1; i > -1; i--) {
             if (!commands[i]) {
                return null;
             }
             if (commands[i]._title != "Typing...") {
                return commands[i]._title;
             }
           }
        }
     }

The second function is to get the last command name from the undo manager, excluding the "Typing..." which is also registered there.
Please note that I see some potential problems which I haven't considered yet, you may have some side effects.
This post is more to show you how to work with some of the client side objects / events and methods than to use in real life.

Actually I am 99.99999 % sure there will be a problem with this code ;). This code was written in abouth 15 - 20 minutes so there should be a bug for sure. I can think of at least two bugs ;).

Here is a video on how this code performs for me:

tinyMCE has the sup - sub issue too

Just to inform you that tinyMCE cannot handle the sup / sub correctly also.

Here is a video:

Telerik radEditor, it is not a bug... but wait ...

Okay, yesterday I wrote a small post showing a small malfunction in telerik radEditor.

The problem was using Sub - Sup...

I got a comment from Tervel - a guy who works on the editor.

As the comment is in Bulgarian I will add a free translation in english (I will ommit hi, pavel and so on and will translate only the things that have relation to this post).

"The way you are changing the commands, it seems to me that the problem is in the browser RichText edit engine.
Sup and Sub commands are sent from telerik radEditor to the browser for further processing." (I think there was something like execCommand("commandName") in JavaScript, this is what he is talking about.

"You can check other editors to verify this behaviour. Strictly, I don't think this is a bug, IE does include sup / sub tags in the context of the current tag, not as a parrent element of the current tag. The result is logical and correct. Whether this is intuitive behavior is another question offcourse. By the way, I think it is."

So here is what I think:
I think that Tervel is right - this is the behavior of IE. And the behavior of FireFox. I checked it too. And this is not a bug.
Yes it is not very intuitive.
Yes it takes another click.

But to me this behavior can be fixed in Telerik making their editor even more intuitive and easy to use.
I don't see any situation in which one would like to have both : sup and sub tags selected. Why would we do that?

Here is what I think can be done in the editor, if someday the guys have some spare time:

Click on sup scnario:
1. Check if the sub command is added (probably it will be but just check for sure).
2. If yes - unselect it.

Same can happen for sub.

Here is a video in which I am trying to input formula with two variables:



And last but not least - this is not an issue for the editor. I just wanted to share my opinion as Tervel left comment.

And once again - we love radEdit ;).

Small bug in telerik radEditor

This one I found while I was playing with the telerik radEditor:



I don't think it is a big deal. You can live with it. Still I consider telerik radEditor one of the best web editors available.

Microsoft SQL Management Studio - Saving changes is not permitted error message.

If you are using Microsoft SQL Management Studio 2008 you may have across this message while trying to edit a table in database:

Saving changes is not permitted. The changes you have made require the following tables to be dropped and re-created. You have either made changes to a table that can't be re-created or enabled the option Prevent saving changes that require the table to be re-created.



It is so self exlpanatory still a lot of people have problems to solve it.



You can follow the steps bellow to fix this:

Select "Options" from the Tools menu:



Then Uncheck the "Prevent saving changes that require table re-creation" option and click OK:

MCTS : Windows applications achieved today!

I got this badge officially today:



I am already entitled as a MCPD: Web Applicaionts but I wanted to achieve the MCPD : Enterprise Developer also so I needed to pass the windows thing.
In order to get there I only need to pass one more exam - the Distributed Applications exam.
Wish me luck!

Test images

Few pictures ...

Your site suddenly stops to save cookies?

I am currently developing an application. One of the requirements is the user to be able to change the language. I added a dropdown to hold the languages. Upon change a cookie is sent to the client with the language selected so when the user visits the site next time his / her language can be auto adjusted. It worked as a charm until today.

It suddenly stopped. I was wondering who to blame, when I saw a small baloon tooltip on the taskbar. It said I am running out of disk space ;).
I deleted my cookies in IE and everything started working correctly again.

(I just wonder if the disk space was the reason why under Firefox worked fine?)

Telerik RadSkinManager doesn't persist the Skin.

If you programatically change the Telerik RadSkinManager Skin property it won't get persisted in the key you added.
This is because probably in telerik asumed if there is no skin chooser the skins won't change and will be loaded from the markup. It is not a bad decision.
However, you may find yourself in need to programatically change the skin and want it persisted.
To do the things tidy I did a small code to persist the skin where it should be persisted.
Here is the code:
        switch (rsMgr.PersistenceMode)
        {
           case RadSkinManagerPersistenceMode.Cookie:
             // Create a cookie to persist the skin selection for the session only:
             HttpCookie cookieSkin = new HttpCookie(rsMgr.PersistenceKey, rsMgr.Skin);
             Response.Cookies.Add(cookieSkin);
             break;
           case RadSkinManagerPersistenceMode.Session:
             // Create a session variable with the same name:
             Session[rsMgr.PersistenceKey] = rsMgr.Skin;
             break;
           case RadSkinManagerPersistenceMode.ViewState:
             // View state variable:
             ViewState[rsMgr.PersistenceKey] = rsMgr.Skin;
             break;
        }

where rsMgr is RadSkinManager.
Now you may paste this code in a method and call this method after you programatically assign skin to the manager. I needed this because I wanted to allow the user to change from some of the skins (not all of them) I couldn't find a way to only hide few skins and display others so I can use the standard functionality of the SkinChooser proerty so I added my own RadCombobox with the skins I want displayed.

Hope this helps someone out there...

Nice little tool to help me with twitter.

I created a small twitter software what it does is to check each hour if I am listening to Winamp, get the song if possible and write it in twitter for me and the people who are eventually interested in what I am listening.
Here is the deal:



You can download it from here:
TWamp - Nice little twitter software

You can follow me on twitter from the following url:
My twitter profile

Please note: TWamp isn't very user friendly. You need to get along with it in order to use it ;).

Understanding the recursion.

Here is the golden rule to understand the recursion:
"In order to understand recursion one must first understand recursion."

Microsoft Office Word automation in C# - How to add table to the document?

The following C# code will create a new document, add a table to it and ask the user to save it. Document will look like this:



The following code will add a table in word and then ask the user to provide a filename to save the document:
        Microsoft.Office.Interop.Word.Application app = new Microsoft.Office.Interop.Word.ApplicationClass();
        app.Visible = false;

        object start = 0;
        object end = 0;
        object oNull = System.Reflection.Missing.Value;

        Document doc = new DocumentClass();
        doc = app.Documents.Add(ref oNull, ref oNull, ref oNull, ref oNull);

        Table tbl = doc.Tables.Add(doc.Range(ref start, ref end), 10, 2, ref oNull, ref oNull);
        Random rnd = new Random();
        for (int i = 0; i < 10; i++)
        {
           tbl.Rows[i + 1].Cells[1].Range.Text = "Run# :" + ((int)i + 1).ToString();
           tbl.Rows[i + 1].Cells[2].Range.Text = "Value :" + rnd.Next(0, 2000).ToString();
        }

        object oFalse = false;
        app.Visible = true;
        try
        {
           doc.Save();
        }
        catch (Exception ex)
        {
           if (ex.Message.ToLower().IndexOf("command failed") == -1)
           {
             throw ex;
           }
        }
        app.Quit(ref oFalse, ref oFalse, ref oFalse);

What we done is to create a new document, a new table, and fill the table with random values.
Seems very easy but not quite sure how well document :).

ASP.NET ProgressBar to show percentage

I did this today during my lunch time break: (sorry about the bad quality but couldn't figure out how to ask YouTube not to resize

it :).

It is ugly and unoptimized yet but I hope I will be able to refactor it soon and make it as a user control.

Another post to follow when this happens.

Cannot have multiple items selected in a DropDownList. Why is this ASP.NET / C# exception rised?

This is a common exception. It happens when you do something like:

        ListItem li1 = new ListItem();
        li1.Text = "Item 1";
        li1.Value = "id1";
        li1.Selected = true;
        ListItem li2 = new ListItem();
        li2.Text = "Item 2";
        li2.Value = "id2";
        li2.Selected = true;
        ddTest.Items.Add(li1);
        ddTest.Items.Add(li2);

Let's explain what is going on.
We created a ListItem, set its name and value and make it to be selected.
Then we created another ListItem, again set its value and name and set it to be selected.

When we add both ListItems the DropDownList confuses about which one should be selected and throws an exception. But why? Because there is another control - ListBox, which allows multiple selection. If we create a ListBox on the form and add the following code in the code behind:

        ListItem li1 = new ListItem();
        li1.Text = "Item 1";
        li1.Value = "id1";
        li1.Selected = true;

        ListItem li2 = new ListItem();
        li2.Text = "Item 2";
        li2.Value = "id2";
        li2.Selected = true;

        lb1.SelectionMode = ListSelectionMode.Multiple;
        lb1.Items.Add(li1);
        lb1.Items.Add(li2);

We will run with no errors and both items will be selected. The problem with the DropDownList control is that shares almost the same functionality with the ListBox and for that reason they both inherit the same base objects.

But the DropDownList doesn't have the ability to display multiple items so ASP.NET team decided to throw an exception when such situation occurs.

This can be confusing in more complicated code, but it is definatelly better than selecting the last item which was marked as "selected" or the first one or something like that. Luckily there are safer ways to select an item without having to worry if there is already selected item or not.

You can use DropdownList.SelectedIndex or DropdownList.SelectedValue properties to mark selected item in a safe manner. So if in the firs example we wanted to select the item with id2 we can use the following code:

        ListItem li1 = new ListItem();
        li1.Text = "Item 1";
        li1.Value = "id1";

        ListItem li2 = new ListItem();
        li2.Text = "Item 2";
        li2.Value = "id2";

        ddTest.Items.Add(li1);
        ddTest.Items.Add(li2);

        ddTest.SelectedValue = "id2";

I commonly use this as in most cases I know which value should I select but don't know which index it has.
Now, there is a situation in which you may want to select by index and this in my imagination is the following situation:
Imagine you have the above DropDownList but you want it to be optional. This means that you need to have an item with empty value or value that means "null" to you. Imagine that this value is already inserted in the DropDownList. You know it will always be the first item. Here is the snippet:

        ListItem liNull = new ListItem();
        liNull.Text = "-- Please Select an Item --";
        liNull.Value = "";

        ListItem li1 = new ListItem();
        li1.Text = "Item 1";
        li1.Value = "id1";

        ListItem li2 = new ListItem();
        li2.Text = "Item 2";
        li2.Value = "id2";

        // Someone selected item in the code:
        ddTest.SelectedValue = "id1";

        ddTest.Items.Add(liNull);
        ddTest.Items.Add(li1);
        ddTest.Items.Add(li2);

        // We will select the first one which is "-- Please Select an Item --"
        ddTest.SelectedIndex = 0;

But in such cases we can take advantage of the default DropDownList behaviour (the DropDownList will select the first item if there are no items selected explicitly). So if you need the first item selected you can simply clear the selection and ASP.NET will select it for you. But how?
By using the ClearSelection() method. It does what it says - it clears the selected item.
Here is the last snippet:

        ListItem liNull = new ListItem();
        liNull.Text = "-- Please Select an Item --";
        liNull.Value = "";

        ListItem li1 = new ListItem();
        li1.Text = "Item 1";
        li1.Value = "id1";

        ListItem li2 = new ListItem();
        li2.Text = "Item 2";
        li2.Value = "id2";

        // Someone selected item in the code:
        ddTest.SelectedValue = "id1";

        ddTest.Items.Add(liNull);
        ddTest.Items.Add(li1);
        ddTest.Items.Add(li2);

        // We will be sure that everything is clean
        // and will expect ASP.NET to select the first item
        // by default:
        ddTest.ClearSelection();