【笔记】11.21 前端的兼容性

作者: 程小E | 来源:发表于2016-11-21 20:02 被阅读29次

【笔记】11.21 前端的兼容性
前端笔记HTML
11.21 前端学习
C3-目录→兼容性
使用webpack的注意点
兼容性测试
兼容性测试 | 原来有这么多种
前端兼容性
前端兼容性
Ajax Axios

1.案例1

问题原因：子级的宽度会撑开父级设置好的宽度

解决方案：将子级的宽度设置小于父级元素的宽度

盒模型一定要计算准确，否则在IE下会出现问题

2.案例2

问题原因：元素浮动时，如果元素需要宽度撑开，需要给里面的块元素添加浮动才行

（注意：内容是块元素才会有此问题）

解决方案：给里面的内容加上浮动

3.案例3

问题原因：在IE6/7下，元素通过浮动排在同一行，如果其中一个元素没有设置浮动，则会出现间隙

解决方案：给这行元素都加浮动

4.案例4

问题原因：在IE6下元素的高度如果小于19px,会被当做19p处理

解决方案：设置overflow:hidden;

5.案例5

问题原因：IE6不支持dotted和dashed边框

6.案例6

问题原因：当父级设置了边框后，子级的margin依然无效

解决方案：设置zoom:1(设置内容加载时的初始倍率)

触发IE6的hasLayout最常用的手段

7.案例7

问题原因：在IE6下双边距的BUG

块元素有浮动并且横向有margind的时候，横向的margin会扩大两倍，形成双边距；

解决方案：设置display:inline;

8.问题原因：margin-left一行中最左侧的第一个元素具有双边距

mragin-right一行中最右侧的第一个元素具有双边距

解决方案：设置display:inline;

9.问题原因：在IE6/7下，li本身没有浮动，li里面的内容有浮动，li下会产生间隙

解决方案：1）给li加浮动（会对标准服务器产生影响）

2）给li加vertical-align

10.基于案例9，同时触发最小高度和li的问题

问题原因：在IE6下，最小高度的BUG和li的间隙共存的时候，使用vertical-align是无效的。

解决方法：给li同时设置overflow:hidden和flow:left

(这种情况下标准游览器是会出现问题的，一般给li设置固定宽度可以解决)

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
ul{
margin:0;
padding:0;
list-style: none;
width: 300px;
}
li{
width: 300px;
list-style: none;
height: 12px;
border:1px solid #000;
/*float: left;*/
overflow: hidden;
float: left;
}
a{
width: 100px;
height: 12px;
float: left;
background-color: red
}
span{
width: 100px;
height: 12px;
float: right;
background-color: blue;
}
</style>
</head>
<body>
<ul>
<li>
<a href="javascript:viod(0)"></a>
<span></span>
</li>
<li>
<a href="javascript:viod(0)"></a>
<span></span>
</li>
<li>
<a href="javascript:viod(0)"></a>
<span></span>
</li>

</ul>
</body>
</html>

11.案例11

问题原因：IE6下的文字溢出BUG

子元素的宽度和父级元素的宽度如果相差小于3px,两个浮动元素中间有注释或者内联元素的时候，就会出现文字溢出，内联元素越多，溢出越多

解决方法：用块标签把注释或内联元素包裹起来

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box{
width: 400px;
}
.left{
float: left;
}
.right{
float: right;
width: 400px;
}
/*文字溢出

*/
</style>
</head>
<body>
<div class="box">
<div class="left"></div>
<span></span>
<span></span>
<div class="right">李先生真帅</div>
</div>
</body>
</html>

12.案例12

问题原因：当一行子元素的宽度跟父级元素的宽度相差超过3px,或者子元素元素不满行的时候，最后一行的子级元素的margin-bottom会失效

解决方案：计算好总数

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box{
border:10px solid red;
/* float: left;*/
width: 600px;
}
.box div{
width: 100px;
height: 100px;
background-color: blue;
border:5px solid #000;
margin: 20px;
float: left;
display: inline;
}
</style>
</head>
<body>
<div class="box">
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
</div>
</body>
</html>

13.案例13

问题原因：当浮动元素和绝对定位元素是兄弟关系时，绝对定位会失效

解决方案：套多一层div,不让起成兄弟关系

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box{
width: 200px;
height: 200px;
border:1px solid #000;
position: relative;
}
a{
position: absolute;
width: 40px;
height: 40px;
background-color: red;
right: 20px;
top:20px;
}
ul{
width: 150px;
height: 150px;
background-color: yellow;
margin: 0 0 0 50px;
padding: 0;
float: left;
display: inline;
}
</style>
</head>
<body>
<div class="box">
<ul></ul>
<a href="javascript:void(0)"></a>
</div>
</body>
</html>

14.案例14

问题原因：子元素有相对定位，父级没有相对定位的时候，父级设置overflow包不住子级元素

解决方案：给父级元素也设置相对定位

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box{
width: 200px;
height: 200px;
border:1px solid #000;
/*右侧有个滑动条*/
overflow: auto;
position: relative;
}
.div{
width: 150px;
height: 300px;
background-color: red;
position: relative;
left: 20px;
top: 20px;
}
</style>
</head>
<body>
<div class="box">
<div class="div"></div>
</div>
</body>
</html>

15.案例十五

问题原因：如果绝对定位的父级宽

和高是奇数的时候，子级元素会有1px的偏差

解决方案：找美工改为偶数

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box{
width: 201px;
height: 201px;
border:1px solid #000;
position: relative;
}
span{
width: 20px;
height: 20px;
background-color: yellow;
position: absolute;
right: -1px;
bottom: -1px;
}
</style>
</head>
<body>
<div class="box">
<span></span>
</div>
</body>
</html>

16.方案16

问题原因：IE6中不存在固定定位，只有绝对定位

解决方案：只能通过JS模拟该效果

17.案例17

问题原因：IE中不认识opacity

解决方案：filter(opacity=50)

18.案例18

问题原因：输入型表单控件上下会有1px的间隙

解决方案：给input加浮动

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<style>
.box{
width: 200px;
height: 32px;
border: 1px solid #000;
}
input{
width: 100px;
height: 30px;
border: 1px solid red;
margin:0;
padding: 0;
float: left;
}
</style>
<body>
<div class="box">
<input type="text">
</div>
</body>
</html>

19.案例19

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
body{
background-color: blue;
}
</style>
</head>
<body>
<img src="img/1.png" alt="" class="qwe">
</body>
<script type="text/javascript" src="js/ceshi.js"></script>
<script type="text/javascript">
DD_belatedPNG.fix(".qwe");
</script>
</html>

需要加入的JS文件

/**
* DD_belatedPNG: Adds IE6 support: PNG images for CSS background-image and HTML <IMG/>.
* Author: Drew Diller
* Email: drew.diller@gmail.com
* URL: http://www.dillerdesign.com/experiment/DD_belatedPNG/
* Version: 0.0.8a
* Licensed under the MIT License: http://dillerdesign.com/experiment/DD_belatedPNG/#license
*
* Example usage:
* DD_belatedPNG.fix('.png_bg'); // argument is a CSS selector
* DD_belatedPNG.fixPng( someNode ); // argument is an HTMLDomElement
**/

/*
PLEASE READ:
Absolutely everything in this script is SILLY. I know this. IE's rendering of certain pixels doesn't make sense, so neither does this code!
*/

var DD_belatedPNG = {
ns: 'DD_belatedPNG',
imgSize: {},
delay: 10,
nodesFixed: 0,
createVmlNameSpace: function () { /* enable VML */
if (document.namespaces && !document.namespaces[this.ns]) {
document.namespaces.add(this.ns, 'urn:schemas-microsoft-com:vml');
}
},
createVmlStyleSheet: function () { /* style VML, enable behaviors */
/*
Just in case lots of other developers have added
lots of other stylesheets using document.createStyleSheet
and hit the 31-limit mark, let's not use that method!
further reading: http://msdn.microsoft.com/en-us/library/ms531194(VS.85).aspx
*/
var screenStyleSheet, printStyleSheet;
screenStyleSheet = document.createElement('style');
screenStyleSheet.setAttribute('media', 'screen');
document.documentElement.firstChild.insertBefore(screenStyleSheet, document.documentElement.firstChild.firstChild);
if (screenStyleSheet.styleSheet) {
screenStyleSheet = screenStyleSheet.styleSheet;
screenStyleSheet.addRule(this.ns + '\\:*', '{behavior:url(#default#VML)}');
screenStyleSheet.addRule(this.ns + '\\:shape', 'position:absolute;');
screenStyleSheet.addRule('img.' + this.ns + '_sizeFinder', 'behavior:none; border:none; position:absolute; z-index:-1; top:-10000px; visibility:hidden;'); /* large negative top value for avoiding vertical scrollbars for large images, suggested by James O'Brien, http://www.thanatopsic.org/hendrik/ */
this.screenStyleSheet = screenStyleSheet;

/* Add a print-media stylesheet, for preventing VML artifacts from showing up in print (including preview). */
/* Thanks to Rémi Prévost for automating this! */
printStyleSheet = document.createElement('style');
printStyleSheet.setAttribute('media', 'print');
document.documentElement.firstChild.insertBefore(printStyleSheet, document.documentElement.firstChild.firstChild);
printStyleSheet = printStyleSheet.styleSheet;
printStyleSheet.addRule(this.ns + '\\:*', '{display: none !important;}');
printStyleSheet.addRule('img.' + this.ns + '_sizeFinder', '{display: none !important;}');
}
},
readPropertyChange: function () {
var el, display, v;
el = event.srcElement;
if (!el.vmlInitiated) {
return;
}
if (event.propertyName.search('background') != -1 || event.propertyName.search('border') != -1) {
DD_belatedPNG.applyVML(el);
}
if (event.propertyName == 'style.display') {
display = (el.currentStyle.display == 'none') ? 'none' : 'block';
for (v in el.vml) {
if (el.vml.hasOwnProperty(v)) {
el.vml[v].shape.style.display = display;
}
}
}
if (event.propertyName.search('filter') != -1) {
DD_belatedPNG.vmlOpacity(el);
}
},
vmlOpacity: function (el) {
if (el.currentStyle.filter.search('lpha') != -1) {
var trans = el.currentStyle.filter;
trans = parseInt(trans.substring(trans.lastIndexOf('=')+1, trans.lastIndexOf(')')), 10)/100;
el.vml.color.shape.style.filter = el.currentStyle.filter; /* complete guesswork */
el.vml.image.fill.opacity = trans; /* complete guesswork */
}
},
handlePseudoHover: function (el) {
setTimeout(function () { /* wouldn't work as intended without setTimeout */
DD_belatedPNG.applyVML(el);
}, 1);
},
/**
* This is the method to use in a document.
* @param {String} selector - REQUIRED - a CSS selector, such as '#doc .container'
**/
fix: function (selector) {
if (this.screenStyleSheet) {
var selectors, i;
selectors = selector.split(','); /* multiple selectors supported, no need for multiple calls to this anymore */
for (i=0; i<selectors.length; i++) {
this.screenStyleSheet.addRule(selectors[i], 'behavior:expression(DD_belatedPNG.fixPng(this))'); /* seems to execute the function without adding it to the stylesheet - interesting... */
}
}
},
applyVML: function (el) {
el.runtimeStyle.cssText = '';
this.vmlFill(el);
this.vmlOffsets(el);
this.vmlOpacity(el);
if (el.isImg) {
this.copyImageBorders(el);
}
},
attachHandlers: function (el) {
var self, handlers, handler, moreForAs, a, h;
self = this;
handlers = {resize: 'vmlOffsets', move: 'vmlOffsets'};
if (el.nodeName == 'A') {
moreForAs = {mouseleave: 'handlePseudoHover', mouseenter: 'handlePseudoHover', focus: 'handlePseudoHover', blur: 'handlePseudoHover'};
for (a in moreForAs) {
if (moreForAs.hasOwnProperty(a)) {
handlers[a] = moreForAs[a];
}
}
}
for (h in handlers) {
if (handlers.hasOwnProperty(h)) {
handler = function () {
self[handlers[h]](el);
};
el.attachEvent('on' + h, handler);
}
}
el.attachEvent('onpropertychange', this.readPropertyChange);
},
giveLayout: function (el) {
el.style.zoom = 1;
if (el.currentStyle.position == 'static') {
el.style.position = 'relative';
}
},
copyImageBorders: function (el) {
var styles, s;
styles = {'borderStyle':true, 'borderWidth':true, 'borderColor':true};
for (s in styles) {
if (styles.hasOwnProperty(s)) {
el.vml.color.shape.style[s] = el.currentStyle[s];
}
}
},
vmlFill: function (el) {
if (!el.currentStyle) {
return;
} else {
var elStyle, noImg, lib, v, img, imgLoaded;
elStyle = el.currentStyle;
}
for (v in el.vml) {
if (el.vml.hasOwnProperty(v)) {
el.vml[v].shape.style.zIndex = elStyle.zIndex;
}
}
el.runtimeStyle.backgroundColor = '';
el.runtimeStyle.backgroundImage = '';
noImg = true;
if (elStyle.backgroundImage != 'none' || el.isImg) {
if (!el.isImg) {
el.vmlBg = elStyle.backgroundImage;
el.vmlBg = el.vmlBg.substr(5, el.vmlBg.lastIndexOf('")')-5);
}
else {
el.vmlBg = el.src;
}
lib = this;
if (!lib.imgSize[el.vmlBg]) { /* determine size of loaded image */
img = document.createElement('img');
lib.imgSize[el.vmlBg] = img;
img.className = lib.ns + '_sizeFinder';
img.runtimeStyle.cssText = 'behavior:none; position:absolute; left:-10000px; top:-10000px; border:none; margin:0; padding:0;'; /* make sure to set behavior to none to prevent accidental matching of the helper elements! */
imgLoaded = function () {
this.width = this.offsetWidth; /* weird cache-busting requirement! */
this.height = this.offsetHeight;
lib.vmlOffsets(el);
};
img.attachEvent('onload', imgLoaded);
img.src = el.vmlBg;
img.removeAttribute('width');
img.removeAttribute('height');
document.body.insertBefore(img, document.body.firstChild);
}
el.vml.image.fill.src = el.vmlBg;
noImg = false;
}
el.vml.image.fill.on = !noImg;
el.vml.image.fill.color = 'none';
el.vml.color.shape.style.backgroundColor = elStyle.backgroundColor;
el.runtimeStyle.backgroundImage = 'none';
el.runtimeStyle.backgroundColor = 'transparent';
},
/* IE can't figure out what do when the offsetLeft and the clientLeft add up to 1, and the VML ends up getting fuzzy... so we have to push/enlarge things by 1 pixel and then clip off the excess */
vmlOffsets: function (el) {
var thisStyle, size, fudge, makeVisible, bg, bgR, dC, altC, b, c, v;
thisStyle = el.currentStyle;
size = {'W':el.clientWidth+1, 'H':el.clientHeight+1, 'w':this.imgSize[el.vmlBg].width, 'h':this.imgSize[el.vmlBg].height, 'L':el.offsetLeft, 'T':el.offsetTop, 'bLW':el.clientLeft, 'bTW':el.clientTop};
fudge = (size.L + size.bLW == 1) ? 1 : 0;
/* vml shape, left, top, width, height, origin */
makeVisible = function (vml, l, t, w, h, o) {
vml.coordsize = w+','+h;
vml.coordorigin = o+','+o;
vml.path = 'm0,0l'+w+',0l'+w+','+h+'l0,'+h+' xe';
vml.style.width = w + 'px';
vml.style.height = h + 'px';
vml.style.left = l + 'px';
vml.style.top = t + 'px';
};
makeVisible(el.vml.color.shape, (size.L + (el.isImg ? 0 : size.bLW)), (size.T + (el.isImg ? 0 : size.bTW)), (size.W-1), (size.H-1), 0);
makeVisible(el.vml.image.shape, (size.L + size.bLW), (size.T + size.bTW), (size.W), (size.H), 1 );
bg = {'X':0, 'Y':0};
if (el.isImg) {
bg.X = parseInt(thisStyle.paddingLeft, 10) + 1;
bg.Y = parseInt(thisStyle.paddingTop, 10) + 1;
}
else {
for (b in bg) {
if (bg.hasOwnProperty(b)) {
this.figurePercentage(bg, size, b, thisStyle['backgroundPosition'+b]);
}
}
}
el.vml.image.fill.position = (bg.X/size.W) + ',' + (bg.Y/size.H);
bgR = thisStyle.backgroundRepeat;
dC = {'T':1, 'R':size.W+fudge, 'B':size.H, 'L':1+fudge}; /* these are defaults for repeat of any kind */
altC = { 'X': {'b1': 'L', 'b2': 'R', 'd': 'W'}, 'Y': {'b1': 'T', 'b2': 'B', 'd': 'H'} };
if (bgR != 'repeat' || el.isImg) {
c = {'T':(bg.Y), 'R':(bg.X+size.w), 'B':(bg.Y+size.h), 'L':(bg.X)}; /* these are defaults for no-repeat - clips down to the image location */
if (bgR.search('repeat-') != -1) { /* now let's revert to dC for repeat-x or repeat-y */
v = bgR.split('repeat-')[1].toUpperCase();
c[altC[v].b1] = 1;
c[altC[v].b2] = size[altC[v].d];
}
if (c.B > size.H) {
c.B = size.H;
}
el.vml.image.shape.style.clip = 'rect('+c.T+'px '+(c.R+fudge)+'px '+c.B+'px '+(c.L+fudge)+'px)';
}
else {
el.vml.image.shape.style.clip = 'rect('+dC.T+'px '+dC.R+'px '+dC.B+'px '+dC.L+'px)';
}
},
figurePercentage: function (bg, size, axis, position) {
var horizontal, fraction;
fraction = true;
horizontal = (axis == 'X');
switch(position) {
case 'left':
case 'top':
bg[axis] = 0;
break;
case 'center':
bg[axis] = 0.5;
break;
case 'right':
case 'bottom':
bg[axis] = 1;
break;
default:
if (position.search('%') != -1) {
bg[axis] = parseInt(position, 10) / 100;
}
else {
fraction = false;
}
}
bg[axis] = Math.ceil( fraction ? ( (size[horizontal?'W': 'H'] * bg[axis]) - (size[horizontal?'w': 'h'] * bg[axis]) ) : parseInt(position, 10) );
if (bg[axis] % 2 === 0) {
bg[axis]++;
}
return bg[axis];
},
fixPng: function (el) {
el.style.behavior = 'none';
var lib, els, nodeStr, v, e;
if (el.nodeName == 'BODY' || el.nodeName == 'TD' || el.nodeName == 'TR') { /* elements not supported yet */
return;
}
el.isImg = false;
if (el.nodeName == 'IMG') {
if(el.src.toLowerCase().search(/\.png$/) != -1) {
el.isImg = true;
el.style.visibility = 'hidden';
}
else {
return;
}
}
else if (el.currentStyle.backgroundImage.toLowerCase().search('.png') == -1) {
return;
}
lib = DD_belatedPNG;
el.vml = {color: {}, image: {}};
els = {shape: {}, fill: {}};
for (v in el.vml) {
if (el.vml.hasOwnProperty(v)) {
for (e in els) {
if (els.hasOwnProperty(e)) {
nodeStr = lib.ns + ':' + e;
el.vml[v][e] = document.createElement(nodeStr);
}
}
el.vml[v].shape.stroked = false;
el.vml[v].shape.appendChild(el.vml[v].fill);
el.parentNode.insertBefore(el.vml[v].shape, el);
}
}
el.vml.image.shape.fillcolor = 'none'; /* Don't show blank white shapeangle when waiting for image to load. */
el.vml.image.fill.type = 'tile'; /* Makes image show up. */
el.vml.color.fill.on = false; /* Actually going to apply vml element's style.backgroundColor, so hide the whiteness. */
lib.attachHandlers(el);
lib.giveLayout(el);
lib.giveLayout(el.offsetParent);
el.vmlInitiated = true;
lib.applyVML(el); /* Render! */
}
};
try {
document.execCommand("BackgroundImageCache", false, true); /* TredoSoft Multiple IE doesn't like this, so try{} it */
} catch(r) {}
DD_belatedPNG.createVmlNameSpace();
DD_belatedPNG.createVmlStyleSheet();