推荐回答(4个)
什么是 JavaScript?
JavaScript 被设计用来向 HTML 页面添加交互行为。
JavaScript 是一种脚本语言(脚本语言是一种轻量级的编程语言)。
JavaScript 由数行可执行计算机代码组成。
JavaScript 通常被直接嵌入 HTML 页面。
JavaScript 是一种解释性语言(就是说,代码执行不进行预编译)。
所有的人无需购买许可证均可使用 JavaScript。
JavaScript 能做什么?
JavaScript 为 HTML 设计师提供了一种编程工具
HTML 创作者往往都不是程序员,但是 JavaScript 却是一种只拥有极其简单的语法的脚本语言!几乎每个人都有能力将短小的代码片断放入他们的 HTML 页面当中。
JavaScript 可以将动态的文本放入 HTML 页面
类似于这样的一段 JavaScript 声明可以将一段可变的文本放入 HTML 页面:document.write("
" + name + "
")
JavaScript 可以对事件作出响应
可以将 JavaScript 设置为当某事件发生时才会被执行,例如页面载入完成或者当用户点击某个 HTML 元素时。
JavaScript 可以读写 HTML 元素
JavaScript 可以读取及改变 HTML 元素的内容。
JavaScript 可被用来验证数据
在数据被提交到服务器之前,JavaScript 可被用来验证这些数据。
JavaScript 可被用来检测访问者的浏览器
JavaScript 可被用来检测访问者的浏览器,并根据所检测到的浏览器,为这个浏览器载入相应的页面。
JavaScript 可被用来创建 cookies
JavaScript 可被用来存储和取回位于访问者的计算机中的信息。
JavaScript是由Netscape公司开发的 基于对象和事件驱动并具有安全性的解释型脚本语言。
主要用于:
1、使页面具有动态效果
2、校验页面用户所填的控件值是否符合程序的规定
3、用Script控制表单标签的显示形式、控制显示样式等
JavaScript是一种客户端的脚本语言,是各种浏览器默认支持的。
如果说HTML定义了页面的结构,CSS美化了页面的样式,那么JavaScript则用来控制页面的行为,它是用来增加页面与用户的交互性的。目前,大多数网页的动态效果,都离不开JavaScript.
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