[翻译]High Performance JavaScript(023)
Data Formats 数据格式
When considering data transmission techniques, you must take into account several factors: feature set, compatibility, performance, and direction (to or from the server). When considering data formats, the only scale you need for comparison is speed.
在考虑数据传输技术时，你必须考虑这些因素：功能集，兼容性，性能，和方向（发给服务器或者从服务器接收）。在考虑数据格式时，唯一需要比较的尺度的就是速度。
There isn't one data format that will always be better than the others. Depending on what data is being transferred and its intended use on the page, one might be faster to download, while another might be faster to parse. In this section, we create a widget for searching among users and implement it using each of the four major categories of data formats. This will require us to format a list of users on the server, pass it back to the browser, parse that list into a native JavaScript data structure, and search it for a given string. Each of the data formats will be compared based on the file size of the list, the speed of parsing it, and the ease with which it's formed on the server.
没有哪种数据格式会始终比其他格式更好。根据传送什么数据、用于页面上什么目的，某种格式可能下载更快，另一种格式可能解析更快。在本节中，我们创建了一个窗口小部件用于搜索用户信息并用四种主流的数据格式实现它。这要求我们在服务器端格式化一个用户列表，将它返回给浏览器，将列表解析成JavaScript数据格式，并搜索特定的字符串。每种数据格式将比较列表的文件大小，解析速度，和服务器上构造它们的难易程度。
XML
When Ajax first became popular, XML was the data format of choice. It had many things going for it: extreme interoperability (with excellent support on both the server side and the client side), strict formatting, and easy validation. JSON hadn't been formalized yet as an interchange format, and almost every language used on servers had a library available for working with XML.
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[转自]http://article.yeeyan.org/view/mouse4x/16540
JSON被公认为浏览器中XML的后继者，它的目标仅仅是成为一种简单、优雅的数据格式，以方便浏览器和服务器之间的数据交换。在完成这一简单任务的过程中，它将引领下一代万维网。
对象简介
看,这就是一个对象:
var myFirstObject ={};
尽管看起来挺简单，然而那些� ......
typeof 是JavaScript的运算符
——返回一个用来表示表达式的数据类型的字符串
typeof[(] expression [)] //typeof语法中的圆括号是可选项
typeof 运算符@import url(../html-vss/msdnie4a.css);
typeof
运算符把类型信息当作字符串返回。typeof
返回值有� ......
A Note on Benchmarking 测试基准说明
Because a regex's performance can be wildly different depending on the text it's applied to, there's no straightforward way to benchmark regexes against each other. For the best result, you need to benchmark your regexes on test strings o ......
第六章 Responsive Interfaces 响应接口
There's nothing more frustrating than clicking something on a web page and having nothing happen. This problem goes back to the origin of transactional web applications and resulted in the now-ubiquitous "please click only once" m ......
第七章 Ajax 异步JavaScript和XML
Ajax is a cornerstone of high-performance JavaScript. It can be used to make a page load faster by delaying the download of large resources. It can prevent page loads altogether by allowing for data to be transferred between the client ......
