尽管现在很多浏览器都支持圆角border-radius这个属性了。
以前做圆角还没那么简单的时候，能用其他方法模拟出圆角，但是不尽完美就是了。
以前在看对话框的时候就疑惑，对话框旁边的小尖角是怎么做的。
看到一篇博客用字符做出来，感觉又get到了技能。
用字符做圆角的话，还是略显粗糙，在浏览器放大到150的时候就显现出来了。
但是尖角的话用作对话的指向确实不错，浏览器兼容也可以。
第二个对话框要实现字符边框效果，关键在于多做一个覆盖层，通过定位的差距遮挡住前一个圆角的绝大部分，只露出圆弧部分实现。
点击看效果demo
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<link rel="styleSheet" href="./demo.css">
<title>Document</title>
<style>
.ml20{
margin: 0 auto;
display: inline-block;
}
.sharp_square{
333px;
height: 110px;
background: #a0b3d6;
position: relative;
color: #a0b3d6;
}
.sharp_top_corner{
line-height: 1;
position: absolute;
font-size: 34px;
top: 32px;
/* right: 80px; */
left: -17px;
}
.sharp_square .quarter_round {
position: absolute;
}
.quarter_round{
display:inline-block;
8px;
height:8px;
overflow:hidden;
font-family:'宋体';
}
.quarter_round span{
display:inline-block;
font-size:16px;
line-height:1;
}
.sharp_square .round_lt {
left: -1px;
top: -1px;
}
.sharp_square .round_rt {
right: -1px;
top: -1px;
}
.sharp_square .round_lb {
left: -1px;
bottom: 0px;
}
.sharp_square .round_rb {
right: -1px;
bottom: 0px;
}
.content_square{
color: #fff;
padding: 20px;
font-size: 14px;
}
.sharp_square .quarter_round span {
background: white;
}
.quarter_round .lt{}
.quarter_round .rt{margin-left:-7px;}
.quarter_round .lb{
position: absolute;
left: 0px;
top: -6px;
}
.quarter_round .rb{
position: absolute;
/* left: 0px; */
top: -5px;
right: -1px;
}
.square_out_border {
472px;
border: 1px solid #dadada;
background: #f8f8f8;
position: relative;
color: #dadada;
}
.square_inner_border {
border: 1px solid #ffffff;
padding: 20px;
font-size: 14px;
color: #333333;
}
.square_top_corner{
line-height: 1;
height: 15px;
font-size: 30px;
position: absolute;
top: -15.99px;
right: 80px;
}
.square_top_corner2 {
line-height: 1;
font-size: 30px;
color: #f8f8f8;
position: absolute;
top: 2px;
right: 0;
}
.square_out_border .round_lt {
left: -3px;
top: -3px;
}
.square_out_border .quarter_round {
position: absolute;
z-index: 1;
}
.quarter_round {
display: inline-block;
8px;
height: 8px;
overflow: hidden;
font-family: '宋体';
}
.square_out_border .quarter_round span {
background: #f8f8f8;
}
.quarter_round .lt {
}
.quarter_round span {
display: inline-block;
font-size: 16px;
line-height: 1;
}
.square_out_border .round_lb {
left: -3px;
bottom: -1px;
}
.square_out_border .round_rb {
right: -2px;
bottom: -1px;
}
.square_out_border .round_rt {
right: -2px;
top: -4px;
}
.square_out_border .round_lt2 {
left: -2px;
top: -2px;
}
.square_out_border .quarter_round2 {
color: #f8f8f8;
z-index: 2;
}
.square_out_border .round_rt2 {
right: -1px;
top: -3px;
}
.square_out_border .quarter_round2 {
color: #f8f8f8;
z-index: 2;
}
.square_out_border .round_lb2 {
left: -2px;
bottom: 0px;
}
.square_out_border .quarter_round2 {
color: #f8f8f8;
z-index: 2;
}
.square_out_border .round_rb2 {
right: -1px;
bottom: 0px;
}
.square_out_border .quarter_round2 {
color: #f8f8f8;
z-index: 2;
}
.square_out_border .quarter_round2 span {
background: none;
}
.method4{
float: left;
}
.con1{
float: left;
}
.method3{
margin: 0 auto;
}
.method3 .zxx_ul_image{
display: inline-block;
margin-left: 100px;
}
</style>
</head>
<body>
<div class="demo-container">
<div class="header">
<i>
<b>字符圆角和尖角实现对话框</b>
</i>
</div>
<div class="method-title">
对话框
</div>
<div class="method-container">
<div class="method4">
<ul class="zxx_ul_image">
<li>
<img src=".././images/monkey.jpg" />
</li>
</ul>
</div>
<div class="ml20 con1">
<div class="sharp_square mt20">
<span class="sharp_top_corner">◄</span>
<span class="quarter_round round_lt"><span class="lt">●</span></span>
<span class="quarter_round round_rt"><span class="rt">●</span></span>
<span class="quarter_round round_lb"><span class="lb">●</span></span>
<span class="quarter_round round_rb"><span class="rb">●</span></span>
<div class="content_square"><span>以四分之一实体圆填充四个角，添加尖角符，实现带尖角的实色圆角矩形。</span></div>
</div>
</div>
<br style="clear:both">
</div>
<div class="method-container">
<div class="method3">
<ul class="zxx_ul_image">
<li>
<img src=".././images/insect.jpg" />
</li>
</ul>
</div>
<div class="ml20">
<div class="square_out_border mt20">
<span class="square_top_corner">◆
<span class="square_top_corner2">◆</span>
</span>
<span class="quarter_round round_lt">
<span class="lt">●</span>
</span>
<span class="quarter_round round_rt">
<span class="rt">●</span>
</span>
<span class="quarter_round round_lb">
<span class="lb">●</span>
</span>
<span class="quarter_round round_rb">
<span class="rb">●</span>
</span>
<div class="square_inner_border">
以四分之一实体圆填充四个角，重复一次，1像素错位。添加尖角符，2像素上下错位，矩形双层标签，实现最终的双边框效果。
</div>
<span class="quarter_round quarter_round2 round_lt2">
<span class="lt">●</span>
</span>
<span class="quarter_round quarter_round2 round_rt2">
<span class="rt">●</span>
</span>
<span class="quarter_round quarter_round2 round_lb2">
<span class="lb">●</span>
</span>
<span class="quarter_round quarter_round2 round_rb2">
<span class="rb">●</span>
</span>
</div>
</div>
</div>
</div>
</body>
</html>
google下效果图:
ie11效果图
