什么是AJAX？
Ajax,shorthand for Asynchronous JavaScript and XML,is a web development technique for creating interactive web applications. The intent is to make web pages feel more responsive by exchanging small amounts of data with the server behind the scenes,so that the entire web page does not have to be reloaded each time the user requests a change.This is meant to increase the web page's interactivity,speed,and usability.
The Ajax technique uses a combination of:
•XHTML (or HTML) and CSS,for marking up and styling information.
•The DOM accessed with a client-side scripting language,especially ECMAScript implementations such as JavaScript and JScript,to dynamically display and interact with the information presented.
•The XMLHttpRequest object is used to exchange data asynchronously with the web server. In some Ajax frameworks and in certain situations,an IFrame object is used instead of the XMLHttpRequest object to exchange data with the web server,and in other implementations,dynamically added <script> tags may be used.
•XML is sometimes used as the format for transferring data between the server and client,although any format will work,including preformatted HTML,plain text,JSON and even EBML. These files may be created dynamically by some form of server-side scripting.
Like DHTML,LAMP and SPA,Ajax is not a technology in itself,but a term that refers to the use of a group of technologies.
JSON
JavaScript Object Notation (JSON) is a lightweight format for representing
objects and their state. Major technology providers,such as Yahoo WS
and Microsoft ASP.NET,have chosen JSON for client-server data exchange
as an alternative to XML,because it can be parsed more easily than XML.
For example,JSON objects can be de-serialized by simply passing them to the JavaScript eval function.
LoadRunner支持的AJAX框架
LoadRunner支持的AJAX框架比较少，以下内容摘自http://www.wilsonmar.com/ajax_rec.htm：
HP has stated that they support these frameworks for AJAX functions:
-
- Atlas 1.0.10920.0/ASP.NET AJAX (All controls) (developed using Visual Studio 2005). LoadRunner 9.10 supported the Atlas 2.0 version in Visual Studio 2005.
- This is one generation behind the ASP.NET 3.5 AJAX AjaxControlToolkit shown on the their sample website. However,I have been able to use LoadRunner 9.51 to work with many MS AJAX 3.5 controls even though some controls are not being created during recording.
- Scriptaculous 1.8 — Autocomplete,Reorder List,and Slider
- Atlas 1.0.10920.0/ASP.NET AJAX (All controls) (developed using Visual Studio 2005). LoadRunner 9.10 supported the Atlas 2.0 version in Visual Studio 2005.
HP advertises that VuGen supports these frameworks at the "engine level",implying that VuGen will create Web Click and Script LoadRunner functions,but not LoadRunner's AJAX specific functions:
-
- Prototype 1.6
- Google Web Toolkit (GWT) 1.4
I've heard that additional licensing is needed for LoadRunner to support the Infragistics library. What is the HP product code for this,if it exists???
LoadRunner的AJAX函数
LR9.0：
VuGen supports recording for the following ASP.NET AJAX controls: Accordion,Collapsible Panel,Rating,and Slider.
| Emulates a user collapsing or expanding sections on a web page. |
|
LR9.5：
The supported frameworks for AJAX functions are:
➤ Atlas 1.0.10920.0/ASP.NET AJAX—All controls
➤ Scriptaculous 1.8—Autocomplete,and Slider
VuGen supports the following frameworks at the engine level. This implies
that VuGen will create standard Web Click and Script steps,but not AJAX
specific functions:
➤ Prototype 1.6
➤ Google Web Toolkit (GWT) 1.4
LoadRunner测试AJAX的例子
以asp.net ajax的在线samples为例：
http://www.asp.net/AJAX/AjaxControlToolkit/Samples/Slider/Slider.aspx
测试其中的slider，LoadRunner可以录制下脚本，并调用ajax_slider函数来处理slider控件的行为：
web_browser("Slider.aspx",
DESCRIPTION,
ACTION,
"Navigate=http://www.asp.net/AJAX/AjaxControlToolkit/Samples/Slider/Slider.aspx",
LAST);
ajax_slider("Slider",
"Framework=atlas",
"ID=ctl00_SampleContent_Slider1",
"UserAction=SetValue",
"Value=100",
LAST);
执行JavaScript的方法
使用web_browser函数，可以通过给EvalJavaScript属性赋值来执行javaScript语句，例如访问DOM，用EvalJavaScriptResultParam属性可以把语句执行的结果存入参数：
web_browser("keyId_Get",
"EvalJavaScript=document.getElementById(/"ctl00_SampleContent_Slider1_BoundControl/").innerText;",
"EvalJavaScriptResultParam=strValue",
LAST);
lr_output_message(lr_eval_string("{strValue}"));
