只是一个绘制图形的容器,除了id、class、style等属性外,还有height和width属性。在>元素上绘图主要有三步: 1.获取元素对应的DOM对象,这是一个Canvas对象;2.调用Canvas对象的getContext()方法,得到一个CanvasRenderingContext2D对象;3.调用CanvasRenderingContext2D对象进行绘图。图形组合:•globalAlpha: 设置或返回绘图的当前 alpha 或透明值 该方法主要是设置图形的透明度,这里就不具体介绍。•globalCompositeOperation: 设置或返回新图像如何绘制到已有的图像上,该方法有以下属性值:下面是一个小示例,可以通过点击改变组合效果: 1. 有关图形组合的文章推荐10篇 简介:<canvas></canvas>只是一个绘制图形的容器,除了id、class、style等属性外,还有height和width属性。在<canvas>>元素上绘图主要有三步: 1.获取<canvas>元素对应的DOM对象,这是一个Canvas对象;2.调用Canvas对象的getContext()方法,得到一个CanvasRenderingC... 2. XML DOM对象方法的实例解析 简介:async 属性 作 用 async 属性表示是否允许异步的下载。 基本语法 boolValue = XMLDocument.async;XMLDocument.async = boolValue; 说 明 布尔值是可擦写的(read/write),如果准许异步下载,值为True;反之则为False。 3. 具体介绍如何在IE中创建DOM并载入XML的详情 简介:Microsoft在JavaScript中引入了用于创建ActiveX对象的ActiveXObject类,通过该类可以创建XML DOM对象的实例,代码如下: 4. HTML5新特性之Mutation Observer代码详解 简介:Mutation Observer(变动观察器)是监视DOM变动的接口。当DOM对象树发生任何变动时,Mutation Observer会得到通知。 5. 使用jQuery进行组件开发完整例子详解 简介:使用jQuery进行组件开发和使用纯JavaScript脚本(不使用框架)原理基本类似,特别是公共方法的组织是一样的。不同点是,jQuery使用了插件机制,通过$()直接进行操作对象(DOM元素)绑定,然后对DOM元素或HTML代码进行绑定事件等的操作。另一个不同点则是把jQuery当做工具来使用,用来创建DOM对象,快速查找指定DOM对象等。例子测试通过。初级简单示例,只实现了增 6. XML中的树形结构与DOM文档对象模型的示例代码(图) 简介:这篇文章主要介绍了XML中的树形结构与DOM文档对象模型,文中举了JavaScript解析DOM对象的例子,需要的朋友可以参考下 7. JavaScript中的DOM操作很慢的原因图文代码详细介绍 #Introduction: I have always heard that DOM is very slow and it is necessary to operate the DOM as little as possible, so I wanted to further explore why everyone is like this. He said that he studied some information online and compiled it here. First of all, the DOM object itself is also a js object, so strictly speaking, it is not that operating this object is slow, but that after operating this object, some browser behaviors will be triggered, such as layout and paint. The following mainly introduces these browser behaviors and explains how a page is finally presented. In addition, it also explains some bad practices and some optimization solutions from the perspective of code. How does the browser render... 8. Why is DOM operation said to be very slow Introduction: I have always heard that DOM is very slow and it is necessary to operate DOM as little as possible, so I wanted to further explore why everyone said this, and I learned some information online, here Sort it out. First of all, the DOM object itself is also a js object... 9. HTML5 canvas basic drawing graphic combination #Introduction: is just a container for drawing graphics. In addition to attributes such as id, class, style, etc., there are also height and width attributes. . There are three main steps for drawing on the > element: 1. Get the DOM object corresponding to the element, which is a Canvas object; 2. Call the getContext() method of the Canvas object to get a CanvasRenderingContext2D object; 3. .Call CanvasRenderi 10. PHP native DOM object manipulation XML Introduction: For operating XML type files, PHP has a set of built-in DOM objects that can be processed. XML operations, from creation, addition to modification and deletion, can be performed using functions in the DOM object. [Related Q&A Recommendations]: javascript - The method of the js object refers to its own object, but the object cannot be found? javascript - Questions about inserting xml objects? html - What is the detailed process of dynamically inserting DOM nodes using javascript? javascript - Can jquery's $ symbol return the default dom object? javascript - About the problem of memory leaks in js