Scour, yet another search engine similar to Crispyweb.com, allows you to search Google, Yahoo, and MSN all from the same page at the same time and filter your search to include only images or videos.
Also it allows user to vote and comment on any given search result.

Depending on the number of votes that a given result receives, its rank will be moved higher or lower down the page. Have a look at Scour - faq to know more about Scour.

In this post, lets see how to use JSON in Ajax-based applications.

AJAX - Asynchronous Javascript and XML is known to IE as ActiveX XMLHTTP object and to the other browsers as XMLHTTPRequest. Ajax uses JavaScript on the page to send requests to a Web server for data. Those requests are HTTP requests just like the one the browser used to retrieve the page. This XMLHttpRequest object can be used to retrieve any kind of data, not just XML. JavaScript can use XMLHttpRequest to retrieve even a plain text file from a Web server and display its contents within a form.

* If it is a plain text, you can access the text by examining the XMLHttpRequest object’s responsetext property.

* If it’s an XML, the XMLHttpRequest object runs an XML parser on the returned document and builds a DOM tree in memory representing the document, and makes that available in the responseXML property.

We know that JSON is just a string of text and not an object in and of itself. So, to make it useful, it has to be converted into a JSON object.

Save the below code in JSON.txt

Ex:

var objResult = {"Results":
{”Teachers” : [
{"firstname": "aaa" ,
"lastname" : "h" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 234234234},
{"firstname": "bbb" ,
"lastname" : "t" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 435345345},
{"firstname": "ccc",
"lastname" : "e" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 564564564},
{"firstname": "ddd" ,
"lastname" : "t" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 343465645}
]
}

}

By using the XMLHttpRequest object, you can retrieve the JSON files from within your AJAX-based application. Hope you know how to create an xmlhttp object for all browsers, I’m moving on to the next step of retrieving the JSON data.

xmlhttp.open(”GET”, “JSON.txt”, true);
xmlhttp.onreadystatechange = callback;
xmlhttp.send(null);

The javascript object which is created on the client side is sent via GET or POST method by assiging the JSON string to a variable. The URL-encoded JSON string to the server as part of the HTTP Request. It can also be sent as raw text using the POST method.

function callback()
{
if(xmlhttp.readyState == 4)
{
if(xmlhttp.status == 200)
{
eval(xmlhttp.responseText);
var showResult = “”;
for (var i=0; i < objResults.Results.Teachers.length; i++)
{
showResult += objResults.Results.Teachers[i].firstname+ ” ” +
objResults.Results.Teachers[i].lastname + “<br>”;
}
//To display the result in a div
var teacherdiv= document.getElementById(”teacherdiv”);
teacherdiv.innerHTML = showResult;
}
}
}

eval(xmlhttp.responseText);

eval() invokes the JavaScript compiler. Since JSON is the subset of Javascript, any Javascript compiler is a JSON decoder. It willcorrectly parse the text and produce an object structure. eval() converts the JSON text into JavaScript Object. It tells the Javascript to treat the elements as Name/value Pair. Here, the JSON response comes from the same server. So, there eval() itself is safe to use. If the respose comes from a different server, the parseJSON() should be used.

The next 3 lines of code is to Iterate through the Teachers object array. After parsing each property into a string, the result is displayed in a div.

JSON on the Server Side:

The JSON data can be sent to the server as a name/value pair via GET method. Now, we have a stringified object. To make use of that in the server side, you have to decode the incoming JSON string and convert the result to an object using a JSON parser for the language of your choice.

After doing your server side coding by keeping the response ready, again create an object to store the response data to send the JSON data back to the client. Convert that object to a string and send the string back to the client as a response body. In .NET,

Response.Write(jsonData);

After getting the response from the server side, convert the incoming JSON string into an object again using Javascript JSON parser and proceed whatever you wish to do with that data.

JSON is faster to parse and more easier than XML. JSON being a lightweight data interchange format makes server side class’ objects easily parseable by client side code to show output on browser.

Hope I have given a clear gist of JSON which would have helped you to start developing your web app with JSON. So, be ready to use JSON for your next web2.0 application.

To know more about JSON refer www.json.org.

In this post, we’re going to see how a JSON data can be accessed.
Have a look at the below sample.

var objResult = {”firstname”: “Pavithra” ,
“lastname” : “D” ,
“Phone” : 234234234}

where “objResult” is a JSON Javascript object holding 3 members firstname, lastname and phone.

To access any of the members, we use a dot (.) .

document.write(objResult.firstname);

The above line will give an output : Pavithra.

Lets see how to access the array values in JSON.

var objResult =
{”Teachers” : [
{"firstname": "aaa" ,
"lastname" : "h" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 234234234},
{"firstname": "bbb" ,
"lastname" : "t" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 435345345},
{"firstname": "ccc",
"lastname" : "e" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 564564564},
{"firstname": "ddd" ,
"lastname" : "t" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 343465645}
]
}

In this example, an object “objResult” is created containing a single member “Teachers”, which contains an array containing four objects, each containing “firstname”, “lastname”, “email” and “Phone” members.
These members can be retrieved using dot or subscript operators.

Every object is a namespace in JSON. Its set of keys is independent of all other objects, even exclusive of nesting. Also, JSON uses context to avoid ambiguity, just as programming languages do. As I said before, JSON can store objects within objects and arrays within arrays that can also store objects, there is no virtual limit to what a JSON object can store.

document.write(objResult.Teachers[0].firstname); will give an output : aaa
document.write(objResult.Teacher[2].Phone); will give an output : 343465645

From my previous blog, you must have understood that JSON is nothing more than a “name : value” pair assigned within an object.  “name/value” pair is the universal data structure which is supported in all programming language in one form or another.  In short we can say, JSON is mainly for DEFINING DATA STRUCTURES wherease XML lacks data structure definition.

In this post, lets see the difference between XML and JSON syntax.

JSON - Javascript Object Notation is a subset of Object Notation in Javascript. It is a programming language independent data format. It is considered as a Light Weight Data Interchange Format as it is easy for programmers to read and for machines to parse and generate. And if you are familiar with C, C++, C#, Java or javascript syntax, JSON coding is very easy.

JSON can either be an object or an array. Object is an unordered set of “name : value” pairs whereas Array is an ordered set of entities.
Basic  Syntax:

{”string” : “value”}

Ex:

{”firstname” : “Pavithra”}

where, firstname is the name (a string)
Pavithra is the value

An object in JSON begins with ” { ” and ends with ” } ” Squiggly brackets. Each name is followed by a : (colon) and the name/value pairs are separated by a ” , ” (comma).  JSON objects are typed whereas XML data are all strings.  So, the JSON value can be a string, number, boolean (true or false), null, a scientific notation or even an object or an array.

As you can see,  JSON is more readable, especially in the case of multiple values.

{”firstname”: “Pavithra” ,
“lastname” : “D” ,
“Phone” : 234234234}

Also this represents how the data are connected.  XML is also readable but more number of opening and closing tags annoys us a lot.
JSON allows you to represent different things in the same data structure.  Also, grouping records in JSON is more simple.


{”Employee” : [
{"firstname": "aaa" ,
"lastname" : "h" ,
"Phone" : 234234234},
{"firstname": "bbb" ,
"lastname" : "t" ,
"Phone" : 435345345},
{"firstname": "ccc",
"lastname" : "e" ,
"Phone" : 564564564}
]
}

where Employee is a member.  Firstname, lastname, phone are strings(names) and the others are values.

Equivalent XML code

< Employee >
< firstname >aaa</ firstname >
< lastname >h</ lastname >
< phone >234234234</ phone >
< firstname >bbb</ firstname >
< lastname >t</ lastname >
< phone >435345345</ phone >
< firstname >ccc</ firstname >
< lastname >e</ lastname >
< phone >564564564</ phone >
</ Employee >

As you see both the XML and JSON code, you can conclude that both are hierarchical. You can have any number of values inside a value (nested values). The above example represents an array and its records.

An array in JSON is holded by a square brackets. An array begins with ” [ " and ends with " ] ” .
Values are separated by , (comma). The same syntax can be used for multiple arrays also.

var objResult =
{”Teachers” : [ //array starts here
{"firstname": "aaa" ,
"lastname" : "h" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 234234234},
{"firstname": "bbb" ,
"lastname" : "t" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 435345345},
{"firstname": "ccc",
"lastname" : "e" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 564564564},
{"firstname": "ddd" ,
"lastname" : "t" ,
"email" : "sdfsf@sd.com" ,
"Phone" : 343465645}
], //array ends here
“Students” : [
{"firstname": "aaa" ,
"lastname" : "h" ,
"mark" : 45},
{"firstname": "bbb" ,
"lastname" : "t" ,
"mark" : 67}
],
“Non-Teachers” : [
{"firstname": "aaa" ,
"lastname" : "h"},
{"firstname": "bbb" ,
"lastname" : "t"},
{"firstname": "ccc",
"lastname" : "e"}
]
}

where “objResult” is a JSON Javascript object which hold 3 members: Teachers, Students and Non-Teachers. These are arrays with multiple values. See the diagramatic representation of the above code to understand better.

In XML you can use any name you want for an element but in JSON you CANNOT use Javascript reserved keywords as it is a native Javascript format. Also, Names are not allowed to start with a number; the entire name may not include any special characters except an underscore or dollar sign; and it cannot be a duplicate of a previously used name within the same object.

I’ll explain how the JSON data can be accessed easily, in the upcoming blog.

Long time No blog… As usual, I have the same reason for not writing for such long time.

I’m back to blogging with something interesting and pretty new stuff JSON - a Data Interchange Format (where I’m landed up currently in my Technology walk through (though not mastered anything yet ) ). JSON is ofcourse, a bit old data format, which is used by Yahoo! in some of its web services and in Google’s web protocols.

But for those who are hearing JSON for the first time, here is a gist of JSON, which is a recent buzzword in Ajax context.
Before exploring JSON, let me give an intro on data formats. Data Formats are used for sending and receiving informations in your asynchronous application.

some of the data formats

• Plain Text
• XML

Before getting into the reason for using JSON, lets see how the other data formats work.

Plain Text Data Format

Plain Text sends and receive data in the form of name/value pairs.

Ex: firstname=Pavithra

firstname=Pavithra&lastname=D&email=pavi@gmail.com

This is more simple way of interchanging data. Plain Text is the most easier way for data interchange which occupies less space and can be sent through GET requests. Also the information doesn’t get lost when the program goes away. You can very well extract the information from a plain text document even if the program is lost.

XML Data Format

If Plain text does most of the things which we want, why XML data format? Plain text files are the smallest, so they can be fetched faster, but the processing is quite slow because you need to parse then in actual Javascript code loops. Ofcourse XML is also a Plain Text format. But it makes the plain Text format even easier by making it self-describing, such that you have metadata inside the file that you can use to extract out the actual semantic meaning of the data in the file, XML comes into context.

XML has a better processing speed when compared to Plaintext data format. XML turned out to be a better choice for the servers that need to send multiple pieces of information to your application. XML is more commonly used for responses to Ajax applications, rather than requests from Ajax applications.

Why not XML?

Okay, Plain Text has some disadvantages. But when XML is considered as the best, why not XML? Well, when using XML, you’re essentially getting the data from the application using JavaScript and stuffing it into a data format. JavaScript being a data manipulation language, moves and manipulates data from Web forms and puts it into a format that can be easily sent to a server-side program.

The objects in the JavaScript language are used to represent data, and more than that just moves
data from Web forms into requests. In this case, it’s more pain to extract data from the objects in JavaScript and then stuff that data into plain text (name/value pairs) or XML. This can be resolved if the Javascript object is converted to data and sent as a part of an asynchronous request. Here is where JSON peeps up.

Atlast JSON:

JSON - Javascript Object Notation is also a type of data format which makes the data and objects move around the application in an easier way. JSON was invented by Doug Crockford - a Yahoo Javascript Architect.

JSON allows you to transform a set of data represented in a JavaScript object into a string that you can easily pass from one function to another, or from a Web client to a server-side program in the case of asynchronous applications.
JSON lets you to call a simple function and get your data, formatted and ready for use. With other data formats, it’s your job to handle the conversion between the raw data and the formatted data. Even while using an API like DOM that provides a function to convert its own data structure into text, you need to learn the API and use that API’s objects. JSON being a javascript format, doesnt require any API or toolkits to work within javascript. JSON string is easily interpreted by JavaScript.

Hope I have covered the basics of JSON. But still, I know you are mussed up. JSON can clearly be differentiated from XML only by exploring even more, as the difference between JSON and XML is negligible. In my next post, I’ll explain about the Name/value pairs in JSON, its syntax and how it is different from other data format.

I have gone through so many forums discussing about the Object tag issue in IE6. The issue was that IE6 does not support Object tag and if Flash content has to be displayed, then dynsrc is the only option. But I faced a different issue with Object tag in IE6. I wanted a Flash banner to be linked to a site. Instead of using the code “on (release) { getURL(”www.aaa.com”) }”  in ActionScript , I tried the below HTML code,

<a href="aaa.com"><Object ......></object></a>

Ofcourse, this is not the proper way of linking a page to a flash. But, just tried and this was working fine in IE7 and not in IE6. I guessed that this should be the same issue “IE6 does not support Object tag”.  So I tried many methods to make it work both in IE6 and IE7. But all in vain. Later I found out the problem. It was really stupid. The issue was object tag cannot be nested inside a tag. This was fixed when I added a div between a tag and object tag. Even div shouldnt be nested within a!!! But why is this working? Also, how the former code works fine in IE7? Is this called an enhancement in IE7? Really funny!

Title Element also plays an important role in Search Engine Optimization. Every webpage must have a Title.
<title> SEO and Title Element </title>

The title must have two or three of your site’s keywords which should enumerate what your site is all about. It is recommended to have the title less than 64 characters as it will be truncated if long. The Title should be relevent to your page’s content as this will be the one displayed with description when your site is listed in the search results and this will be the one which will be read first. Search engines have title as an important factor to rank your site. Avoid using symbols and special characters. It is better to give few words in the Title as grammer also matters. Two or three words doesnt require grammar check. Also, Title will be the default bookmark name while user bookmarks your site.

This is my first blog on SEO and I’d like to start from META tags. We all know the use of “meta” tag. The name itself defines that it gives a meta information about our page. Lets start from the base.
What is meta information? How is this playing an important role in SEO?
Description and Keywords are the meta informations.

Why should we give Description and Keyword in the meta tags?
There is something called ODP (Open Directory Project). ODP is nothing but a web directory of Internet resources. Its like a library hierarchically arranged by subject - from broad to specific. Your website will be evaluated by a team of experts and included in this directory. They provide a title and description for your site based on their evaluation. When your site is listed in the Search result in any search engine, by default this description will be displayed as a snippet for the web result. Search engines like Google, MSN uses ODP while Yahoo! uses Yahoo! directory. In order to avoid the Search engines to get ODP data, you’ll have to specify your own description for your site. The reason for avoiding this is, the description given by ODP is outdated and will not have the current status of your website. This is the reason to have our own updated description.

This is the right place to use meta tags where you can give the description and you can assure the search engines not to use data from ODP and Yahoo! directory. To avoid ODP data, just include robots meta tags. This robots meta tag is used to exclude the content. It is used only when you are unable to upload or control robots.txt file. The robots.txt file will have some set of instructions for robots(spiders) to index the content of your site. This file should be placed in the root directory of your site. The robots meta tags are just the replacement of this txt file.
This is how you give the robots meta tag,

<meta name=”robots” content=”NOODP”>
NOODP - NO ODP data

This is supported by Google, MSN.

In the case of Yahoo!, you can use NOYDIR to avoid Yahoo! directory data.

<meta name=”robots” content=”NOYDIR”>
NOODP - NO Yahoo! Directory

To specifically prevent any particular search engine to use the ODP data, you’ll have to specify the meta tag with the following names
<meta name=”googlebot” content=”NOODP”>

<meta name=”slurp” content=”noydir”>

<meta name=”msnbot” content=”NOODP”>

But it will take some time or may be days to see your description. In the case of using the default description, you dont have to worry about site ranking. Site ranking is no way related to this since it is based on the search algorithm and not on how your site is classified in the web directory.

This is how meta tag bids an important role in SEO.

I’ve been using my Acer laptop for almost a year now but still dint know many things which I am not supposed to do when my laptop is in battery mode. Today I came to know few stuff and I am sure it will be useful for a lot of you who are still a Trainee in using Laptops

DOs and Donts while using laptops in battery mode

• Avoid running CD/DVDs
• Avoid using Pen drives (this consumes more battery power)
• Avoid scanning your laptops (Anti-virus)
• Avoid playing 3D Games/ watching movies
• Avoid multi tasking (MS Excel, Word consumes less battery power)
• Always use your laptops in a cool place. 

Better leave it plugged in whenever possible.

Following these, will increase the life of your laptop’s battery.

It is hard to think of a password which is easy-to-remember. I have many email accounts and unique passwords. I often forget those and keep on trying all possibilites since the passwords are no way related to the account type. It would be nice if someone hints a strong, easy-to-remember but hard to guess
passwords for us. But we dont rely on others for passwords rite?

So, better use Passwordbird which is launched only for generating passwords for the information you provide. Just answer few questions about you and get the password.

Dont like the password?? Ask the bird to grind out a new one or, you can choose to start over completely with a new set of words and dates.

No registration, no request for your emailid and more secured.