JavaScript维度的相关内容

文章 2020-05-15 来自：开发者社区

从JS引擎角度剖析DataFlux前端性能，多维度提升网站用户体验

性能与体验一直都是前端开发中老生常谈的话题，也是开发出一款优秀web应用必须要考虑的问题。随着google V8引擎的发布，Node的诞生，前端能做的事情也越来越多，浏览器的能力也被无限放大和利用。如何在能够在完成迭代需求的基础上，逐步优化网站性能以及体验，充分利用浏览器的能力突破性能瓶颈，提升交互体验，趋优网站亲和性，则成为了一个前端开发必须逾越的鸿沟。这篇文章我们结合DataFlux前端应....

文章 2017-12-16 来自：开发者社区

JS编程建议——53：小心使用数组维度

建议53：小心使用数组维度在JavaScript中，数组在默认状态下是不会初始化的。如果使用[]运算符创建一个新数组，那么此数组将是空的。如果访问的是数组中不存在的元素，则得到的值将是undefined。因此，在JavaScript程序设计中应该时刻考虑这个问题：在尝试读取每个元素之前，都应该预先设置它的值。但是，如果在设计中假设每个元素都从一个已知的值开始（如0），那么就必须预定义这个数组。我....

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更新时间 2024-04-30 14:09:01

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