DHTML 笔记

DHTML 不是 W3C 标准。
DHTML 结合 CSS 和 JavaScript。

元素必须指定位置属性（relative相对 或者 absolute绝对）。
然后设置下面的属性：
left - the element's left position
top - the element's top position
visibility - specifies whether an element should be visible or hidden
z-index - the element's stack order
clip - element clipping
overflow - how overflow contents are handled

position:relative 指定元素的位置相对于当前元素。
position:absolute 指定元素的位置距离窗口页边。
visibility:visible 元素可见。
visibility:hidden 元素隐藏。
z-index 相当于三维坐标系中的 Z 轴。

滤镜（过滤器？^_^）
使用滤镜时应该总是指定 width 属性。
h1
{
width:100%;
filter:glow;
}

如果 background-color 属性不被设置成 transparent（透明）， 一些滤镜的属性将不能工作。
Property Argument Description Example

alpha	opacity finishopacity style startx starty finishx finishy	Allows you to set the opacity of the element	filter:alpha(opacity=20, finishopacity=100, style=1, startx=0,  starty=0, finishx=140, finishy=270)
blur	add direction strength	Makes the element blur	filter:blur(add=true, direction=90, strength=6);
chroma	color	Makes the specified color transparent	filter:chroma(color=#ff0000)
fliph	none	Flips the element horizontally	filter:fliph;
flipv	none	Flips the element vertically	filter:flipv;
glow	color strength	Makes the element glow	filter:glow(color=#ff0000, strength=5);
gray	none	Renders the element in black and white	filter:gray;
invert	none	Renders the element in its reverse color and brightness values	filter:invert;
mask	color	Renders the element with the specified background color, and transparent foreground color	filter:mask(color=#ff0000);
shadow	color direction	Renders the element with a shadow	filter:shadow(color=#ff0000, direction=90);
dropshadow	color offx offy positive	Renders the element with a dropshadow	filter:dropshadow(color=#ff0000, offx=5, offy=5, positive=true);
wave	add freq lightstrength phase strength	Renders the element like a wave	filter:wave(add=true, freq=1, lightstrength=3, phase=0, strength=5)
xray	none	Renders the element in black and white with reverse color and brightness values	filter:xray;

background-attachment:scroll 页面空闲时滚动。
background-attachment:fixed 页面空闲时固定。

DOM 文档对象模型

事件处理
Event Occurs when...

onabort	a user aborts page loading
onblur	a user leaves an object
onchange	a user changes the value of an object
onclick	a user clicks on an object
ondblclick	a user double-clicks on an object
onfocus	a user makes an object active
onkeydown	a keyboard key is on its way down
onkeypress	a keyboard key is pressed
onkeyup	a keyboard key is released
onload	a page is finished loading. Note: In Netscape this event occurs during the loading of a page!
onmousedown	a user presses a mouse-button
onmousemove	a cursor moves on an object
onmouseover	a cursor moves over an object
onmouseout	a cursor moves off an object
onmouseup	a user releases a mouse-button
onreset	a user resets a form
onselect	a user selects content on a page
onsubmit	a user submits a form
onunload	a user closes a page