Tanzim Saqib on .NET discovery

Web 2.0 applications are widely developed. These applications often work with third party contents, aggregate them, make various use of them and then make something useful and meaningful to the users. For the past few years, developers were also engaged with such endeavors and a lot of their websites have not addressed performance issues, thus resulting in an unpleasant experience to the users.

Performance is a vast area and great results can never be achieved by a silver bullet. This article explores some of the key performance issues that can occur while developing a Web 2.0 portal using server side multithreading and caching. It also demonstrates model driven application development using Windows Workflow Foundation.

URL: http://dotnetslackers.com/articles/aspnet/SevenWaysToDoPerformanceOptimizationOfAnASPNET35Web20Portal.aspx

It's a very common bad practice. We often iterate through array, build HTML contents and keep on concatenating into certain DOM element. Every time you execute the block of code under the loop, you create the HTML markups, discover a div, access the innerHTML of a div, and for += operator you again discover the same div, access its innerHTML and concatenate it before assigning.

function pageLoad()
{
    var links = ["microsoft.com", "tanzimsaqib.com", "asp.net"];
    
    $get('divContent').innerHTML = 'The following are my favorite sites:'
    
    for(var i=0; i<links.length; ++i)
        $get('divContent').innerHTML += '<a href="http://www.' + links[i] + '">http://www.' + links[i] + '</a><br />';
}  

However, as you know accessing DOM element is one the costliest operation in JavaScript. So, it's wise to concatenate all HTML contents in a string and finally assign to the DOM element. That saves a lot of hard work for the browser.

function pageLoad()
{
    var links = ["microsoft.com", "tanzimsaqib.com", "asp.net"];
    var content = 'The following are my favorite sites:'
    
    for(var i=0; i<links.length; ++i)
        content += '<a href="http://www.' + links[i] + '">http://www.' + links[i] + '</a><br />';
        
    $get('divContent').innerHTML = content;
}