Tech Reflexes

Passing object[] from a webmethod

2010-04-21T10:24:00.000-07:00

A PageMethod returning a object[] will be the ugliest of solutions, you would say. Sometimes, you are forced to code in a not-so-elegant style. And here's one such implementation. If any of you think you can make it better, please leave a comment.

Another solution to this will be to wrap all these objects up into a class and have this as the return type.


public class MyReturnType {
    public ClassA A { get;set; }
    public ClassB B { get;set; }
    public ClassC C { get;set; }
}

and return an instance of MyReturnType (or List for multiple values)

Returning this composite MyReturnType object will be the ideal solution. But in my case, the elements of this class are known only at run time. Typically, this class will need to be build at run time. The easier alternate will be to


[WebMethod]
public object[] GetObjects()
{
   ...
   return new object[] { objA, objB, objC };
}

Tidy your HTML code on Visual Studio

2010-04-13T08:48:00.000-07:00

I, so absolutely love this shortcut! (Next only to Ctrl + k,c)

There's a way to tidy up your HTML source code view on your Visual Studio
- Ctrl + k,d and Ctrl + k,f

While Ctrl + k,d formats the whole page, Ctrl + k,f formats the selected area on the page

Implementing ICallbackEventHandler

2010-04-07T07:37:00.000-07:00

Asynchronous communication with the server is also made possible by implementing the ICallbackEventHandler interface (System.Web.UI.ICallbackEventHandler). ICallbackEventHandler sends user defined elements back to the server to process and the output is return in the form of a string back to the client, thus enabling a partial postback without the UpdatePanel.

These are the steps in implementing ICallbackEventHandler interface:

Inherit ICallbackEventHandler

Inherit ICallbackEventHandler on the page or the user control where it needs to be implemented. The code for this will be


public partial class Contributions : System.Web.UI.UserControl, ICallbackEventHandler

As a result, two functions needs to be implemented in the code

public void RaiseCallbackEvent(string eventArgument)
public string GetCallbackResult()

RaiseCallbackEvent() is automatically called when there is a Callback event. The GetCallbackResult() is called in sequence right after the RaiseCallbackEvent() is processed.


public string GetCallbackResult()

   {

       return result;

   }

This method here just ejects HTML code into the page to set the server datetime.


 public void RaiseCallbackEvent(string eventArgument)

   {

       result = "document.getElementById('txtPercentage').innerHTML = '" + DateTime.Now.ToLongTimeString() + "'";

   }

The method RaiseCallbackEvent() here, just passes the server datetime back to the client. This can typically be any server process and the result variable being set.

ASPX/ASCX page

Below is the HTML for the usercontrol. The Callback, in this case will be initiated from a user control.


<%@ Control Language="C#" AutoEventWireup="true" CodeFile="Contributions.ascx.cs" Inherits="Contributions" %>

The above code will just create a CallbackEvent on onclick() event of the HTML button control.

Code File Wireup

The code for the server side OnPageLoad() will be,


if (!IsPostBack)

   {

       string callback = Page.ClientScript.GetCallbackEventReference(this, "arg", "DisplayResults", "context");

       string script = "function CallBack(arg,context){" + callback + ";}";

       Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "CB", script, true);

   }

GetCallbackEventReference() obtains a reference to the client function that when invoked, initiates a client callback to the server.


public string GetCallbackEventReference(

	string target,

	string argument,

	string clientCallback,

	string context,

	string clientErrorCallback,

	bool useAsync

)

target - The server control that initiates the callback. The control 'must' implement the ICallbackEventHandler interface

argument - Argument that is passed from the client script to the server for processing

clientCallback - The client script method that needs to be called after the server callback is processed

context - Client script that is evaluated on the client before initiating a callback to the server

useAsyn - When true initiates the call in the asynchronous fashion

function CallBack(arg,context) - is the client side script that invokes the GetCallbackEventReference() with the required arguments.

All this should set you going for your implementation of ICallbackEventHandler.

Hello World - iPhone

2009-08-18T11:41:00.000-07:00

I have always been intrigued by iPhone apps and this is a long pending (self-learning) post of a simple 'Hello World' program in iPhone. This blog post serves to let the user get familiar with the iPhone code environment.

Creating a Project

Download XCode along with IPhone's SDK from Apple's website.
Once installed and opened, click File -> New Project
Pick the Application template under iPhone OS category
Select 'View-based application' and click Choose
At this point, it will ask for the Project name -> Save

Once, the Project file is created, it will display all the code files and resources associated with the project. There isn't much now but it is a fully functional application that of course, does nothing. Click on the 'Build & Go' to see the iPhone Simulator open up the application.

XIB files are where the user interface behind the Mac and iPhone application are stored. Double clicking on the MainWindow.xib file will open up the Interface Builder app. This lets the user create the user interfaces. Once the IB loads, it displays a mock iPhone view. The users can select an array of objects (buttons, text boxes and the whole lot of it) from the Tools Library. If the Tools library is not automatically loaded, click Tools -> Libary or (command - shift+command+L)

Interface design

On the Tools Library, make sure Object is selected. And then, in the search box start typing 'text'.
Select TextView and drag it on the mock iPhone area and place it. Double clicking, lets you change the text. Then type the infamous - "Hello World!!"
Close the Interface Builder and select 'Build & Go' on XCode window.

That's the simple 'Hello World!" app on iPhone.

I plan to explore more on iPhone and Objective C and plan to have series of posts. Looking forward to learning more!

Mono for .Net on Mac

2009-07-30T09:05:00.000-07:00

I am a .Net developer and with the new Mac, Mono has been inviting me for a long time now. With my baby's (long!) nap for an hour provided me with the opportunity to try out Mono and blog about it!

Why Mono?

1. A .Net developer since I learn to code - you know how addicted you can get to VS :)

2. A new Mac enthusiast

Steps to start trying out Mono

1. Get the installable from the go-mono site.

2. Run the installer. Mono installs under /Library/Frameworks/Mono.Framework

3. Here comes the famous 'Hello World'!!


using System;
public class Hello
{
static public void Main()
 {
     Console.WriteLine("Hello World, Here I come");
}
}

Note: For those of us .Net developers that hadn't worked in a shell terminal for a long time now, here are some of the notes to freshen up your memory!

1. vi filename - opens the vi editor with the filename
2. to save the file - :w
3. to quit the editor - :q
4. obviously, to save and quit - :wq (although, you would have figured it by now!)

4. Compile the code with - 'gmacs hello.cs'

5. Execute the code with - 'mono hello.exe'

There you go! Your first C# program on a Mac! Though simple, doesn't it thrill you?

Bang! Bang!! - The first time I compile the program - I got the error,

"`System.Console' does not contain a definition for `Writeline'". It took a full thirty seconds to spot the reason for the error - It should have been WriteLine!! Darn, VS has us fully spoiled!

Is C++ really dead?

2009-07-29T12:44:00.000-07:00

Is it?? Read this discussion group thread

Inline Vs. Code Behind

2009-07-29T12:17:00.000-07:00

StackOverflow has this discussion on some code being inline in the aspx page versus it getting into the code behind file.

Well, it made me start thinking. Thinking about it, I used to hate code getting into aspx pages with my colleagues. It led into code getting scattered and ended up losing the control of the code. Somehow, code behind makes it look more natural.

However, in case of a gridview - some people get more code into code behind

<asp:Literal ID="litExample" runat="server"

OnDataBinding="litExample_DataBinding" />

protected void litExample_DataBinding(object sender, System.EventArgs e)

{

Literal lit = (Literal)(sender);

lit.Text = string.Format("{1} - {2}",

Eval("ExampleField").ToString(),

Eval("ExampleField2").ToString());

}

There will be no performance difference on either type of the code. It's more to do with the best practices and to improve the readability of the code.

In this case, I like to keep the code in the aspx page as the code here is more declarative and design oriented.

    Text='<%# Eval("ExampleField").ToString() %>' />

Safari Quirks

2009-06-19T07:26:00.000-07:00

Have you found that Safari opens all links in a new window a little weird. And you can not force Safari to open it in the same window (in a different tab!) - Read this blog post by Nik Fletcher of TUAW to make Safari use the Uni-Window mode!

Wolfram Alpha: Get your answers

2009-05-20T08:56:00.000-07:00

After being dubbed the next Google killer - in one line, Wolfram Alpha is: It is certainly not a Google killer but will make Google really think about how it can improve presenting data.

The introduction screencast left all of us waiting for the launch on 7pm CST on last Friday. The screencast had raised the expectations and scores of thousands were eagerly awaiting its launch. To top the expectations, Wolfram had announced that it will video cast the release, which was a first of the kind for a service with such big expectations. Though it started with a small glitch, the computational knowledge-base search engine did quite well.

Wolfram Alpha is certainly impressive and has raised the bar with how the objective data can be computed in real time and facts presented in a neat format. I typed in some of the queries and Wolfram Alpha handled them exceptionally well:

I did have some no-showers/bloopers:

The Verdict: Wolfram Alpha did amazingly well when given a mathematically corelated input or statistically inclined input. It still has to climb some mountains for Natural Language Processing (NLP).

But given the fact that it is still Alpha, Wolfram Alpha has a long way to go and has shown us all a new dimension. It may not be a immediate threat to Google, but will surely be one to Wikipedia.

Kudos to the team at Wolfram Alpha for a new relevation!

Twitter: I did see the real power of Twitter in action during the Wolfram release. On TweetDesk, I could get a consolidated view on what people were thinking about Wolfram Alpha instantly! Makes me more appreciative of Twitter!

Speed up VS 2005

2009-05-19T09:43:00.000-07:00

VS2005 is always thirsty for more memory. There are a few tricks that could save up some RAM for you.

Speed up the launch of VS2005

Disable the 'Start Page' - Tools->Options->Environment->Startup section
Disable Splash screeen - Properties->Add parameter /nosplash to the target
Close all unnecessary panels and tabs so that the IDE does not reload them on restart

More Options

Turn off 'Track Changes' - Tools -> Options -> Text Editor
Turn off 'Track Active Item' - Tools -> Options -> Projects & Solutions
Turn off 'Auto Populate Toolbox' - Tools -> Options -> Windows Form Designer

HDD speed matters. 7200 r.p.m is better than a 5400 r.p.m. Read here to see why it's important.

And of course, having more memory helps :)

Google Hosted JQuery

2009-05-13T11:49:00.000-07:00

Roughly a year back, Google announced that it would host widely used open source JavaScript Libraries on their Content Distribution Network - jQuery, Prototype, Script.aculo.us, MooTools to name a few. Google suggests the use of their Google AJAX API Loader's google.load() method to gain application speed.

How to use in ASP.Net Application?

This is how the JQuery library could be loaded using Google AJAX API Loader's google.load() method.

There are certainly some benefits using Google's CDN

Caching
Decreased Latency
Convenience

Caching - Better speed
The main advantage of using Google's CDN is they manage all the bug fixes, recent updates and provide a high speed access due to better caching, etc. The simple idea behind this is speed - the user's browser does not have to download multiple copies of JS libraries from different public facing websites.

Decreased latency
Certainly, you could make use of Google's distributed servers to download the JS files from a server located physically close to you.

Convenience
Google takes out the pain of staying upto date with the source code, bug fixes, minifying and version changes.

However, there are certain things that a developer needs to be aware of before taking the road of Google CDN.

What if Google goes down? Will your code be prepared to handle something like this. Well, if you will take care of it, you are all set!
There will be a performance speedup only when the user happens to have those libraries loaded from some other site that uses google’s service

A Good Programmer Cartoon

2009-05-13T11:02:00.001-07:00

DateTime.Now Vs. System.Diagnostics.Stopwatch

2009-04-28T12:12:00.000-07:00

Occasionally all of us, as programmers would like to see how fast or how slow a C# function can execute. I am sure, most of us must have used DateTime.Now for the measurements. Roughly on these lines,


DateTime startTime = DateTime.Now;

// Some Execution Process

DateTime endTime = DateTime.Now;
TimeSpan totalTimeTaken = endTime.Subtract(startTime);

Now, does DateTime.Now accurately measure performance? No, it does not. DateTime.Now, according to MSDN has a resolution of ~16ms, which means it is not very precise.

Environment.TickCount
Another approach would to use system tickcount as kept by Environment.TickCount. This keeps the number of milliseconds since the computer was started. Unfortunately it is stored as a signed int, so every 49 days it is actually counting backwards. We can compensate for this by just taking off the most siginificant bit.

Stopwatch
Another better approach is to use Stopwatch. System.Diagnostics offers Stopwatch that automatically checks for high precision timers. You can check if the Stopwatch is using high-precision timers by checking via Stopwatch.IsHighResolution() method.


Stopwatch swTimer = Stopwatch.StartNew();
//Some execution process here
foo()
swTimer.Stop();

Watch for the difference in the code results


protected void Page_Load(object sender, EventArgs e)
  {
    DateTime  sStartTime, sEndTime;   
    TimeSpan  tsTotalTimeTaken;
       
    sStartTime = DateTime.Now;
 for (long lCount = 0; lCount < 100; lCount++)
      {
        Thread.Sleep(1);
      }//for(int iCount=0; iCount<100; iCount++)
      
      sEndTime = DateTime.Now;

      Stopwatch swTimer = Stopwatch.StartNew();
      
      for (long lCount = 0; lCount < 100; lCount++)
      {
        Thread.Sleep(1);
      }//for(int iCount=0; iCount<100; iCount++)      
      
      swTimer.Stop();
      
      tsTotalTimeTaken = sEndTime.Subtract(sStartTime);      

      Response.Write("Elaspsed Time according to DateTime.Now(): " + tsTotalTimeTaken.Milliseconds + "
");
      Response.Write("Elapsed Time according to StopWatch(): " + swTimer.Elapsed.Milliseconds);
    }

Output:

Wanna be Macbie

2009-04-03T13:45:00.000-07:00

Mac Dream
MacBook has been on my 'Desire List' for sometime now. Everytime I think of indulging myself with the sleek user interface that Apple offers, I push the idea out thinking that its going to be a difficult shift for a ASP.NET developer. Is it really that difficult?

ForeWord: This blog post comes out with no PC vs. Mac argument.This is just research on things needed for a ASP.NET developer treading into Mac waters.

Questions Galore
How can I compile C# code on Mac? Will I have to learn to write code on Objective-C? Should I start using the Cocoa Framework instead of the .NET Framework? Will I still be able to use AJAX.NET on Mac? These are the questions that ring loud and clear in any .NET programmer's mind.

I try to seek answers to these and wish for a Mac soon! :)

BootCamp
BootCamp comes packaged with Mac OS X. This software assists users to install Windows XP and Windows Vista while leaving all the Mac data in place while it creates a separate partition on your drive for Windows. BootCamp even lets you start up the Mac using either of the operating systems.

Parallels and VMWare
Parallels and VMWare are virtualization softwares that help break down the wall between Mac and a PC. Both these products offer a seamless desktop environment between Mac OS X and PC applications.

These virtualization softwares do come with certain performance penalties. See Jeff Atwood ponder problems and discuss solutions.

Decide between Parallels/VMWare and BootCamp

Mono
Mono is a open-source development initiative to develop an open source, UNIX version of Microsoft.NET development platform. Mono includes a CLI (Common Language Infrastructure) virtual machine, a class library that works on CLR and a compiler for C# language.

Everything seems okay, but aren't we still missing something that .NET programmers cannot live without?? Yeah, the Visual Studio has got you hooked onto it - you will not know how much you love this tool until you start missing it! I see the Microsoft guys smiling :)

Here comes MonoDevelop. MonoDevelop is a IDE designed for C# and other .NET languages. Developed code can also be ported on unix machines. Take a look at Screenshots for MonoDevelop, they are really promising.

Mono and AJAX.NET?
Microsoft's ASP.NET AJAX Control Toolkit works on Mono, and is open source (Ms-PL). That doesn't preclude the use of jQuery, though. There are actually several third party AJAX libraries and control toolkits that support Mono, and many are compatible or work in conjunction with ASP.NET AJAX.

You .Net developers, ready for a Mac? :)

Twitter Buzz

2009-03-26T16:13:00.001-07:00

It's been a couple of weeks since I have said - 'I do' to Twitter and I have a couple of interesting observations to make.

Twitter's sweet success
Twitter, with its infamous 140 word limit has carved a niche out for itself in micro-blogging arena. Twitter's growth has been so phenomenal that it has 750,000 user profiles with a whopping 1382% increase in user profiles since last year. Get started in to this world with its own 'Twitter Glossary'.

Who's Tweeting
Adults between the ages of 35 and 49 comprise almost 42 percent of the site's audience - and about 62 percent of them are accessing the site from work. The average user hits Twitter.com about 14 times a month and spends about seven minutes on the site.

Twitter on the move
It could a simple "What are you doing now?". Now, you wonder who would want to know what you do in everyday life? Realistically speaking, will it be just random bragging of an unexceptional life. Rewind to early 2000's and one realizes that the same argument was held when 'Weblogs' were still young in the internet space. Twitter is a platform for social communication. What you do with it depends on 'You'. You could use it for simple 'I did this, I did that sorta stuff' or for something more useful.

You end up following not just people, but their activities and lifestyle in general. Twitter is brevity at its best. It promotes communicating one's thoughts with concise and clear sentences.

Twitter is the latest method of evoking quick answers to your questions. Try posting a question or a musing and you will be surprised to see answers. Twitter is the new age information travel where you follow others without being intrusive.

Twitter creates a sense of virtual world where you have a lifestyle, friends and conversations. It creates the Third World after Home and Work. It is a place where you go to when you are done with family, friends, work and everything else.

Twitter bird feed
The social networking platform is a free for all service right now. There were rumors that Twitter is going to start using advertising platform to start generating revenues. Now, Twitter has confirms that it will soon offer paid premium accounts to businesses.

Time flies with Twitter
Oh! Time does fly fast with Twitter. It leads you onto interesting Tweets, entertaining blog posts, more interesting Tweets and more entertaining stuff - and the world has endless of these. It easily can eat into your productive time. Use it well and it stays your best pal.

Spams Ho!
Where there is a means of communications there are spams and phishers. Watch out for them while you spend your time here.

So the answer to - To Tweet or Not To is - Use it well, or you could end up losing your job in 140 characters or less.

ToTweet Or Not to Tweet...

2009-03-10T10:51:00.000-07:00

To Tweet or Not To Tweet - That's the question my friend....

I am away from work on a maternity leave - will be quite long, a year actually. Gotta spend some time with the little one, right? Absolutely loving it....

So, I am trying to be a regular at my blogging space exploring new things. This is one such expedition - I have always wanted to try out Twitter and see why everyone (on the blog space) has been using it. Is it one of those fads or is it here to stay? Is it a great networking tool that people claim it to be or is it just a 'time-gobbler' and 'productivity-hinder'? Should you really 'Tweet' or is it just a farce?

Please stay by, while I explore and do check again later to see my views on Twitter :)

Frustrating "Local Access Only" Problem - Vista Worries

2009-02-17T10:21:00.000-08:00

Being the 'computer handyman' of the family, I was fiddling with my sister's relatively new notebook that has a Vista Home Basic Edition installed on it. After keeping her notebook, up-to-date with all the security patches, service packs and similar things - the weirdest thing (ok! not something totally weird, if you are used to working on a PC :)!) happened. The notebook lost all contact to the outside world. You got it right! - the notebook lost its wireless connection. I was getting a 'Local Access Only'.

The notebook had Vista Home Basic Edition with SP1 installed. Googling, I realized that this was not an isolated issue but a prevalent problem among Vista users. This is a consolidated list of numerous recommended things I tried, before resolving the issue -

Using Windows Diagnostics Mode to resolve the problem automatically. I received the message that the notebook was unable to acquire a new IP address and was asked to reset the router.
Reset the router and modem individially and reset them together.
Disabled DHCP and assigned a static IP to the notebook
Connected the computer using a wired connection to the modem
Uninstalled and reinstalled the wireless adapters numerous times
Checked to see if the wireless adapters (NIC) had any more updates
Was unable to connect in the safe mode with networking turned on
Turned the IPV6 off to see if that was the issue
Removed Symantec and AVG Anti Virus Software running in the system
Turned Windows Firewall off to make sure that was not holding back the connection.
Turned DHCP broadcast flag to ON in the Registry. Read more in this Microsoft KB Article
Gateway 0.0.0.0 problem. Type 'route print' in the Command Window (Start->Run->Cmd->Enter). If you see a 0.0.0.0 entry against the Default Gateway, enter 'route delete 0.0.0.0' and then press Enter.

After all this, I was all set to 'Restore' the system to a prior date when the Wireless Connection was working perfectly fine - and surprisingly, it did the trick! Go to 'Start->Data backup and Recovery' and select the Restore Point when things were working perfectly ok.

Its true that sometimes, the solution can lie just under your nose and you may overlook it :)

Bottomline - The guess is that, Windows has some software updates that might cause this problem to arise. So, once you have the system restored - you should be able to reinstall the Microsoft updates one by one to get hold of the culprit. I will update this blog with the details once I can pinpoint the software update!

String Vs. StringBuilder classes

2008-11-12T08:04:00.000-08:00

One of the .Net performance efficiency tip that we, developers keep hearing from all quarters is to use StringBuilder over String concatenates.

Now, lets see what actually happens behind the scenes. Are people right when they StringBuilder is better? Does it have a performance edge? If so, when?

Scenario 1:
String Concatenation

String sStringHolder = "";
Random rRandomize  = new Random(150);

DateTime dtStartTime = System.DateTime.Now;
for (int iCount = 0; iCount < 10000; iCount++)
{
 sStringHolder = sStringHolder + "1";
}//for(int iCount=0; iCount<1000; iCount++)
DateTime dtEndTime = System.DateTime.Now;

Trace.WriteLine("Time taken using the Concat operation >> 10000 Iterations: ");
Trace.WriteLine(((TimeSpan)(dtEndTime - dtStartTime)).Milliseconds);

dtStartTime = System.DateTime.Now;
for (int iCount = 0; iCount < 20000; iCount++)
{
 sStringHolder = sStringHolder + "1";
}//for(int iCount=0; iCount<1000; iCount++)
dtEndTime = System.DateTime.Now;

Trace.WriteLine("Time taken using the Concat operation >> 20000 iterations: ");
Trace.WriteLine(((TimeSpan)(dtEndTime - dtStartTime)).Milliseconds);

The first iteration (for 10000 loops) took 46 milliseconds while the second iteration where the loop count doubled (20000 loops) increased almost 9 times (375 milliseconds).

So, what does really go on inside? Why are the results so drastically different?

sStringHolder = sStringHolder + "1";

Strings are immutable, i.e., the value can not modified once it is created. So, in this case three instance of the String objects are created to accommodate the concatenation. When a concat is performed, the old sStringHolder is discarded and a new one created to hold the newly concatenated string. That is the reason why it becomes too expensive.

Scenario 2
StringBuilder Goodness

StringBuilder sbStringHolder = new StringBuilder(50);

dtStartTime = System.DateTime.Now;
for (int iCount = 0; iCount < 50000; iCount++)
{
 sbStringHolder.AppendFormat("{0}", "Hello");
}//for(int iCount=0; iCount < 1000; iCount++)
dtEndTime = System.DateTime.Now;
   
Trace.WriteLine("Time taken using StringBuilder class:AppendFormat >> 50000 iterations: ");
Trace.WriteLine(((TimeSpan)(dtEndTime - dtStartTime)).Milliseconds);

That was 15 milliseconds for a 50000 count iteration! StringBuilder certainly has an edge here.

This advantage that StringBuilder has is due to the fact that the string allocation and copies does not have to be as frequent as a String Concatenate. That's from where the majority of the savings come from. But if the StringBuilder has a buffer that's just right for the string that it holds, it will have to grow on every Append which is as good (or bad) as the string concatenate.

Although, this cannot be taken as a rule of thumb that StringBuilder is always more efficient than a String concatenation - Rico Mariani explains the four different cases.

Big string and small appends
=>It's substantially likely that appends will fit in the slop and so they're fast, this is the best case(buffer size becomes double the string when it no longer fits so on average the slop is half the current string length) (if there are lots of small appends to a big string you win the most using stringbuilder)

Big string and big appends:
=>While the string is comparable in size (or smaller) to the appends stringbuilder won't save you much, if this continues to the point where the appends are small compared to the accumlated string you're in the good case

Small string big appends:
=> bad case, string builder will just slow you down until enough slop has built up to hold those appends, you move to "big string big appends" as you append and finally to "big string small appends" if/when the buffer becomes collossal

Small string, small appends:
=> could be ok if you had a good idea how big your string was going to get and pre-allocated enough so that you have sufficient slop for the appends. You might be able to do better if you just concatenated all the small appends together in one operation.

Otherwise put, if the operation that is to be performed is something like this:
x = f(x) + f(y) + f(z) + f(a) - String Concat is better

If the operation will be something to this effect:
x += f(x);
x += f(y);
x += f(z);
x += f(a) - StringBuilder will suit better in this scenario

The ?? Operator

2008-11-06T08:49:00.000-08:00

Today was my first brush with the ?? operator and was pleasantly surprised by what it can do.


string sString1 = null;
string sString2 = "Hi";
string value = "";

// We would normally it this way
value = sString1 != null ? sString1 : sString2;

// Using ?? operator also called as coalescing
value = sString1 ?? sString2;

// In effect, it could be string
// val = a ?? b ?? c
// - The first non-null value is assigned to val
Response.Write(value);

Chaining ?? operator certainly makes it easier to perform a bunch of comparisons. When the ?? operator is chained, it assigns the value of the first non-null value.

Hourglass (Wait) cursor on page load

2008-10-24T13:40:00.001-07:00

This is another pearl that was figured at work today. There are instances where we might want to turn the cursor into a hourglass symbolizing that the user needs to wait as the page is getting loaded. There are more than one way to achieve this. There are two that comes to my mind (please feel free to add more)

1. Using AJAX - UpdateProgress Extender that displays a wait modal popup extender when the page is getting loaded and ready
2. A simpler approach is to use JavaScript that does exactly this

We are going to see the second approach at work -

function doWait()
{
document.body.style.cursor = 'wait';
}
<body onbeforeunload="doWait();" onunload="doWait();">

Notice the events onbeforeunload() and onunload() events. The reason we use two events is that these events are browser dependent and so to behave well with different browsers, we do this!

Both Mozilla FireFox and Internet Explorer implements onbeforeunload() DOM events.

Another useful function of onbeforeunload() is to alert the user when he leaves the webpage. Read here to know more about this DOM event.

Capitializing first letter of every word

2008-10-14T06:10:00.000-07:00

The ToTitleCase method in .NET is not a part of String class but of TextInfo class that resides in System.Globalization namespace. This method converts the first character of every word into upper case. Here's how to use it,

String sHelpText = "aN eXamPle tEXT";
System.Globalization.CultureInfo oCInfo = System.Threading.Thread.CurrentThread.CurrentCulture;
System.Globalization.TextInfo oTextInfo = oCInfo.TextInfo;

return(oTextInfo.ToTitleCase(sHelpText.ToLower()));

Note: The .ToLower() Method is used to explicitly convert the string into lower case. According to MSDN - the title casing converts the first character into upper case, except for a word that is upper case in entirety. Read more on this here.

Faster Firefox 3.0

2008-10-10T10:05:00.000-07:00

While you were thinking about giving up FireFox due to its speed and memory bloats, Mozilla came out with 3.0 - a relatively faster successor.

Now, is it possible to tweak FireFox 3.0's default settings and make it work at lightening speed? Here are some of FF 3.0 browser tweaks.

For the uninitiated - you don't want to see all the gruesome details of application settings, but still want to experience the speed? Rush ahead to https://addons.mozilla.org/en-US/firefox/addon/9148, install the add-on. From my experience, there is a consistent 30-40% increase in the browser's rendering speed for the web pages. Go on! Try it.

For those of you, who would like to know the nuts and bolts of everything - read on!

HTTP is the application-layer protocol that web pages are transferred with. In HTTP 1.1, multiple requests can be sent before any responses are received. This is known as pipelining. Pipelining reduces page loading times.

1. Open FireFox
2. Type about:config in the address bar and press Enter
3. In the filter bar type network.http.pipelining. Double-click to set it to true
4. Return to the filter bar and type network.http.pipelining.maxrequests. Double-click this option and set its value to 8.
5. Go to the filter bar and type network.http.proxy.pipelining. Once it opens double-click it to set it to true.
6. Right-click Preference Name and create a new Integer value. Enter content.notify.backoffcount in the New integer value pop-up window and click OK.
7. Right-click Preference Name and create a new Boolean value. Enter plugin.expose_full_path in the New boolean value pop-up window and click OK.
8. Right-click Preference Name and create a new Integer value. Enter ui.submenuDelay in the New integer value pop-up window and click OK.

These all the common settings for everyone. Check out below for specifics:

Note: A faster computer means - >513 MB Memory and 1.5 Ghz and a Faster Connection means - DSL/Cable (not dialup)

Forgotten Attachment Detector

2008-09-25T11:38:00.000-07:00

For those few that are not aware of GMail Labs yet - GMail Labs is an experimental ground for trying out the new ideas and features from the Google team. These add-ons may or may not make it to the GMail feature list in future. Meanwhile, it is certainly worthwhile to try our hand at them.

I was awed and pleasantly surprised by this new GMail Labs feature available. Forgotten Attachment Detector warns you about sending an email without attachments. According to Jonathan K, the author of this wonderful piece of code from Google Labs - Forgotten Attachment Detector prompts you if you mention attaching a file, but forgot to do so.

See the prompting feature in action!

This is such a cool feature that it makes me think - how did we miss having this all along on an email client. Kudos to Jonathan and the team at Google labs! This add-on looks for the the word 'attach' or its derivatives in the email before sending it (somehow, it thinks 'attachments' is not one of those and does not prompt for the files to be attachments!!)

If you have still not enabled this Labs feature, take a look at how to enable them

And then enable the Forgotten Attachment Detector - and voila, you are all set!

Modal Popup Extender and flicker issues

2008-09-23T13:35:00.000-07:00

ModalPopup extender is a very convenient and easy tool for designing lightbox style modal popups.

During development, I realized that the contents that go in the modal popup box appear for a split second when the page gets loaded. In repeated tries, I was actually able to grab a screen shot of the strange behaviour.

Look at the contents below the button! They are a part of the modal popup contents. Pretty weird, huh?

To get around this - simply set the popup panel's style to display:none.

And the modal popup extender code

Android - Google's 'Dream'

2008-09-22T06:33:00.000-07:00

Android - another addition to the U.S smart phone industry. The smart phone market boils to two key players - Apple iPhone and it's competitor RIM Blackberry. The irony, however is that nobody even mentions Windows SmartPhones in that list (that has been in the market for quite a while).

Android OS dubbed GPhone, is about to be launched on September 23, 2008 integrated into T-Mobile's HTC phone, and is called 'Dream'. This would definitely spark a fierce competition between Dream and iPhone during the Christmas period.

Built on the Linux kernel, Android is a so-called open platform where nobody is charged for using it on the phone or for building applications on the phone. Though iPhone has a similar set up for its users and developers where millions of iPhone applications have been downloaded - the catch is that, all applications will have to be available only through iTunes store.

The highlights of Android is guessed to be

Mobile OS-Linux that will include a in-built browser, 2D and 3D graphics, SQLite DB, video and audio playback, GSM, Bluetooth, WiFi, 3G wireless, camera, compass, GPS - that's a standard, neat list
QWERTY keyboard based touch screen with haptic feedback (You can feel the bumps of keys and virtual games)
A complete Java based development environment with a plug-in to Eclipse.
Core applications built with OS - GMail, GDocs, Maps
The price tag is guessed to be around $199 to position itself with iPhone, and to be a direct compeititor. There are rumors that it would be $150 for a existing customer account upgrade.

For an Android walk-through, click here and more screenshots here

As always, an average customer knows what he wants to do with a phone: make and receive calls, send and receive text messages and access some basic online information. However, a couple of months into using iPhone, I can see the excessive dependence on information on the go - Maps, search for business in a locality, emails, messengers and increased productivity.

This launch will be closely watched by a users and developers alike. Unlike iPhone, the impact this launch will cause will not be effectively gauged right after the release - it will take sometime to sink into the minds of people as yet another smart phone. This phone will certainly make its impact on the cost of the mobile and its applications.

Google's Chrome

2008-09-09T12:26:00.000-07:00

The first thing that catches the eye in Google Chrome is its minimalist design that gives the feeling of a light weight application. Chrome is built on the existing rendering engine Webkit - framework version of the engine used by Safari and Android.

One thing that I find very interesting is the multi-process design of the application. The application resources are not shared between different tabs and so you will be able to isolate that particular website that eats memory. (Yikes! Now you can tell Youtube.com eats about 280MB of the 300MB browser load - Now that's something, isn't?)

Omnibox
The address bar has in-built auto-suggest feature that helps users to get where they are going. Chrome uses Google Suggest to fetch the suggestions as the user starts to type. It allows access to bookmarks, history, search and much more from the same place. This feature is very similar to the one available in Firefox 3.0

Downloads
Downloading has become much more neat and non-intrusive - no more status bars or pop-up dialogues. This features is again very much similar to the the add-ons available for FF, the difference here is that it is built right into the browser.
Performance
The faster the website is rendered, better is the user experience and thus, better is the performance. Chrome takes advantage from its all new Javascript Engine V8 built from scratch by its Denmark team.

Chrome for Developers

DOM Inspector
The HTML Document Object Model can be viewed in a neatly organized tree structure. This however, is not entirely new to the browser world - FF has it. Although, what's new is the CSS style description on the right.

Chrome Inspector derives a lot of inspiration from FF's Firebug (a FF addon, available for IE also) . Chrome Inspector also has the pictorial resources view of the resources and their load time. This DOM Inspector is certainly a welcome start to inspect/edit the live DOM of any web document or XUL application.

JavaScript Console

Another feature straight out of Firebug is JS Console. To view this console, right-click on the webpage > Inspect Element; then click Show console at the bottom tag of the window.

Chrome finally eases JS debugging by providing us with the much awaited auto-complete feature. This command line tool feature will be more handy when used with 'Breakpoint' debugging - something that is available in Firebug and missing in Chrome.

JS Debugger
Chrome equips us with a command-line JS debugger. I looked around Google Chrome's FAQ for developers and could not find more information on how to use this. I am certain that some developers will surely find this tool powerful, but I am not in that league yet.

Memory Usage
Chrome has surely taken us by storm with this feature - a by-product of their multi-process architecture. Click Developers on the Control the current page icon > Task Manager > Stats for nerds - provides a prolific view of the open tabs and the memory usage. Keep hitting F5 - Refresh to corner out webpages that are leaking memory. This information will certainly be useful for developers to identify memory leaks.

Easter Eggs!
Easter Eggs are hidden, intentional messages in a software or application. They are the most interesting finds when an application gets released! I think many of you would agree with me on this! Here are some of the Easter Eggs I found while looking around

Try these at the Google Chrome's address bar and enjoy!
about:internets
about:stats
about:memory
about:plugins
about:histograms
about:cache
about:dns
about:crash