how to generate barcode in asp.net using c# 6-1. IMPLEMENTING WEB SERVICES FOR LARGE OR SLOW DATA SETS in Font

Paint Code 3 of 9 in Font 6-1. IMPLEMENTING WEB SERVICES FOR LARGE OR SLOW DATA SETS

Source: /client/scripts/jaxson/uimorphing.js (DynamicIterator) intervalId : 0, startIteration : function(direction) { this.intervalId = Thread.startThread( function( direc) { DynamicIterator.shiftArrayElements( direc); }, direction, 500); }, stopIteration : function() { Thread.endThread( this.intervalId); }, Putting the Remaining Pieces of the Client Together Several times I ve referenced the DynamicIterator implementation, which is used to navigate the metadata of the result set. The main role of DynamicIterator is to load the metadata navigational elements, and when the individual elements are referenced, the main data is loaded. I explain the implementation of DynamicIterator in pieces, with the following representation of the initialization of the navigation elements. Source: /client/scripts/jaxson/uimorphing.js var DynamicIterator = { lastElem : null, floatingIframe : null, parentRow : null, initialize : function(floatingIframeID, parentRowID) { this.floatingIframe = document.getElementById(floatingIframeID); this.parentRow = document.getElementById(parentRowID); this.doLayout(); this.getMoreRootElements( 0); }, doLayout : function() { this.floatingIframe.style.width = document.body.clientWidth - 4; this.floatingIframe.style.height = document.body.clientHeight - 104; }, // Other declarations... }; Going back to the beginning of the Implementing the HTML Client section, recall the piece of HTML code that implemented the body.onload event, which called the local Initialize function. In the implementation of Initialize, the DynamicIterator.initialize method is called. Calling DynamicIterator.initialize will cross-reference the HTML user interface elements with the DynamicIterator instance. DynamicIterator.initialize expects two HTML user interface elements: the floating iframe (this.floatingIframe) and the table row (this.parentRow) that contains the navigational elements. DynamicIterator needs these two user interface elements because it loads the data highlighted in the navigational area. After the user interface elements have been assigned to the data members, the doLayout method is called. The purpose of doLayout is to

resize the iframe so that it covers the appropriate client area. And the last method call in DynamicIterator.initialize is the calling of the getMoreRootElements method, which is responsible for loading the metadata navigational elements. In the context of DynamicIterator, the getMoreRootElements method is declared as an empty function similar to the following: getMoreRootElements : function( direction) { } The empty function is a placeholder, and it is expected that the HTML code will declare an implementation. In the case of the HTML code, getMoreRootElements is defined as follows. Source: /client/ajaxrestrecipes/architecture/dynamiclist.html DynamicIterator.getMoreRootElements = function( direction) { if( direction == 0) { var asynchronous = FactoryHttp.getCachedAsynchronous(); asynchronous.settings = { onComplete : function(xmlhttp) { var arrTickers = new Array(); var tickers = JSON.parse( xmlhttp.responseText); for( var c1 = 0; c1 < tickers.length; c1 ++) { arrTickers.push( { text : tickers[ c1], url : "/pyservices/trader/historical/tickers/" + tickers[ c1]}); } DynamicIterator.associateElements( arrTickers); } } asynchronous.get("/pyservices/trader/historical/tickers"); } } In the case of the HTML code, the tickers that represent the metadata used to navigate through the application (as shown in Figure 6-10) are loaded once. Metadata might be unlimited, but often it can be limited to a fixed set size, even if that set size is very large. Looking at the example, each piece of metadata is a ticker that can have one to four letters (on average). If you multiply that number by 1,000 tickers, then you have to download about 4KB 5KB of data (in this era of broadband, downloading 4KB 5KB is trivial). The stock application will allow at most 50 tickers due to technical limitations, so all of the tickers can be downloaded in one request. In the case of our example, getMoreRootElements with a direction of 0 means to download an initial set of metadata elements. How that data is downloaded is the responsibility of the getMoreRootElements implementation. This example uses the Asynchronous class, and the response is encoded as a JSON array. For every ticker found, an object is created where the ticker is combined with a URL and added to the arrTickers array. Once the arrTickers array has been filled with elements, the DynamicIterator. associateElements method is called as follows.