javascript自动按比值显示图片,按比例压缩图片显示

javascript自动按比例显示图片,按比例压缩图片显示

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    <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){
if (typeof(objImg)=='string'){
objImg = $(objImg);
}
var img = new Image();
img.onload = function(){
var hRatio;
var wRatio;
var Ratio = 1;
var w = img.width;
var h = img.height;
wRatio = maxWidth / w;
hRatio = maxHeight / h;
wRatio = wRatio>1?1:wRatio;
hRatio = hRatio>1?1:hRatio;
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 {
Ratio = (wRatio<=hRatio?wRatio:hRatio);
}
if (Ratio<1){
w = w * Ratio;
h = h * Ratio;
}
objImg.height = h;
objImg.width = w;
this.onload = function(){}
}
img.src = objImg.src;
}
    </script>

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    <br />
    原图显示(534 X 800)<br />
    onload="AutoResizeImage(0,0,this)<br />
    <a href="http://p.blog.csdn.net/images/p_blog_csdn_net/feng_sundy/421506/o_09925c7bcead8c60f683298dacf497a6.jpg"
        target="_blank">
        <img src="http://p.blog.csdn.net/images/p_blog_csdn_net/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.csdn.net/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank">
        <img src="http://p.blog.csdn.net/images/p_blog_csdn_net/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.csdn.net/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank">
        <img src="http://p.blog.csdn.net/images/p_blog_csdn_net/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.csdn.net/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank">
        <img src="http://p.blog.csdn.net/images/p_blog_csdn_net/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.csdn.net/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank">
        <img src="http://p.blog.csdn.net/images/p_blog_csdn_net/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.csdn.net/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank">
        <img src="http://p.blog.csdn.net/images/p_blog_csdn_net/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.csdn.net/feng_sundy/archive/2008/06/19/2566028.aspx" target="_blank">
        <img src="http://p.blog.csdn.net/images/p_blog_csdn_net/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 />
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