JS控制图片显示的大小（图片等比例缩放）

最新推荐文章于 2023-12-13 19:20:18 发布
nono4909
最新推荐文章于 2023-12-13 19:20:18 发布
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 
<html xmlns="http://www.w3.org/1999/xhtml">
 
<head>
 
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 
<title>最新javascript自动按比例显示图片，按比例压缩图片显示</title>
 
<script type="text/javascript">
 
function AutoResizeImage(maxWidth, maxHeight, objImg) {
 
    var img = new Image();
 
    img.src = objImg.src;
 
    var hRatio;
 
    var wRatio;
 
    var Ratio = 1;
 
    var w = img.width;
 
    var h = img.height;
 
    wRatio = maxWidth / w;
 
    hRatio = maxHeight / h;
 
    if (maxWidth == 0 && maxHeight == 0) {
 
        Ratio = 1;
 
    } else if (maxWidth == 0) { //
 
        if (hRatio < 1)
 
            Ratio = hRatio;
 
    } else if (maxHeight == 0) {
 
        if (wRatio < 1)
 
            Ratio = wRatio;
 
    } else if (wRatio < 1 || hRatio < 1) {
 
        Ratio = (wRatio <= hRatio ? wRatio : hRatio);
 
    }
 
    if (Ratio < 1) {
 
        w = w * Ratio;
 
        h = h * Ratio;
 
    }
 
    objImg.height = h;
 
    objImg.width = w;
 
}
 
</script>
 
</head>
 
<body>
 
<br />
 
原图显示（534 X 800）<br />
 
onload="AutoResizeImage(0,0,this)<br />
 
<a href="https://p-blog.youkuaiyun.com/images/p_blog_youkuaiyun.com/feng_sundy/421506/o_09925c7bcead8c60f683298dacf497a6.jpg" target="_blank"><img src="https://p-blog.youkuaiyun.com/images/p_blog_youkuaiyun.com/feng_sundy/421506/o_09925c7bcead8c60f683298dacf497a6.jpg" border="0" width="0" height="0" onload="AutoResizeImage(0,0,this)" alt="534 X 800"/></a><br/><br />
 
1.按宽度250压缩,不限制高度 按比例压缩<br />
 
onload="AutoResizeImage(250,0,this)"<br />
 
<a href="http://blog.youkuaiyun.com/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank"><img src="https://p-blog.youkuaiyun.com/images/p_blog_youkuaiyun.com/feng_sundy/421506/o_09925c7bcead8c60f683298dacf497a6.jpg" border="0" width="0" height="0" onload="AutoResizeImage(250,0,this)"  alt="250 X 374"/></a><br /><br />
 
2.按高度250压缩,不限制宽度 按比例压缩<br />
 
onload="AutoResizeImage(0,250,this)"<br />
 
<a href="http://blog.youkuaiyun.com/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank"><img src="https://p-blog.youkuaiyun.com/images/p_blog_youkuaiyun.com/feng_sundy/421506/o_09925c7bcead8c60f683298dacf497a6.jpg" border="0" width="0" height="0" onload="AutoResizeImage(0,250,this)"  alt="166 X 250"/></a><br /><br />
 
3.按高度250宽度250 按比例压缩<br />
 
onload="AutoResizeImage(250,250,this)"<br />
 
<a href="http://blog.youkuaiyun.com/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank"><img src="https://p-blog.youkuaiyun.com/images/p_blog_youkuaiyun.com/feng_sundy/421506/o_09925c7bcead8c60f683298dacf497a6.jpg" border="0" width="0" height="0" onload="AutoResizeImage(250,250,this)"  alt="200 X 300"/></a><br /><br />
 
4.高宽不等比例压缩 （400 X 512）,此时高度不变，会自动按高度的比例压缩。<br />
 
onload="AutoResizeImage(400,512,this)"<br />
 
<a href="http://blog.youkuaiyun.com/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank"><img src="https://p-blog.youkuaiyun.com/images/p_blog_youkuaiyun.com/feng_sundy/421506/o_09925c7bcead8c60f683298dacf497a6.jpg" border="0" width="0" height="0" onload="AutoResizeImage(400,512,this)"  alt="341 X 512"/></a><br /><br />
 
5.高宽不等比例压缩 （300 X 600）,此时宽度不变，会自动按宽度的比例压缩。<br />
 
onload="AutoResizeImage(300,600,this)"<br />
 
<a href="http://blog.youkuaiyun.com/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank"><img src="https://p-blog.youkuaiyun.com/images/p_blog_youkuaiyun.com/feng_sundy/421506/o_09925c7bcead8c60f683298dacf497a6.jpg" border="0" width="0" height="0" onload="AutoResizeImage(300,600,this)"  alt="300 X 449"/></a><br /><br />
 
6.如果图片本来的高度和宽度小于压缩的最大高度和宽度，则不会拉大显示图片（按原图显示）<br />
 
原图444 x 207,压缩为 500 x 600,将保持原图显示<br />
 
onload="AutoResizeImage(500,600,this)"<br />
 
<a href="http://blog.youkuaiyun.com/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank"><img src="https://p-blog.youkuaiyun.com/images/p_blog_youkuaiyun.com/feng_sundy/242776/o_20070410_b7409cd284a0f799a357uePcEFa6ty0X.jpg" border="0" width="0" height="0" onload="AutoResizeImage(500,600,this)"  alt="444 X 207"/></a><br /><br />
 
</body>
 
</html>