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Detailed explanation of how to obtain picture width and height information in php
Detailed explanation of how to obtain picture width and height information in php
所用函数： getimagesize: 取得图像大小 (PHP 3, PHP 4, PHP 5) array getimagesize ( string filename [, array &imageinfo] ) 说明： 索引 0 包含图像宽度的像素值， 索引 1 包含图像高度的像素值。 索引 2 是图像类型的标记：1 = GIF，2 = JPG，3 = PNG，4 = SWF，5 = PSD，6 = BMP，7 = TIFF(intel byte order)，8 = TIFF(motorola byte order)，9 = JPC ，10 = JP2，11 = JPX，12 = JB2，13 = SWC，14 = IFF，15 = WBMP，16 = XBM。这些标记与 PHP 4.3.0 新加的 IMAGETYPE 常量对应。 索引 3 是文本字符串，内容为“height="yyy" width="xxx"”，可直接用于IMG 标记。 用php或js获取图片大小,高宽尺寸.
<?
$arr=getimagesize("images/album_01.gif");
echo $arr[3];
$strarr=explode("\"",$arr[3]);
echo $strarr[1];
?>
<HTML>
<HEAD>
<TITLE>演示图片等比例缩小_bbs.it-home.org</TITLE>
<script>
function Wa_SetImgAutoSize(img)
{
//var img=document.all.img1;//获取图片
var MaxWidth=200;//设置图片宽度界限
var MaxHeight=100;//设置图片高度界限
var HeightWidth=img.offsetHeight/img.offsetWidth;//设置高宽比
var WidthHeight=img.offsetWidth/img.offsetHeight;//设置宽高比
alert("test"+img.offsetHeight+img.fileSize);
if(img.offsetHeight>1) alert(img.offsetHeight);
if(img.readyState!="complete"){
return false;//确保图片完全加载
}
if(img.offsetWidth>MaxWidth){
img.width=MaxWidth;
img.height=MaxWidth*HeightWidth;
}
if(img.offsetHeight>MaxHeight){
img.height=MaxHeight;
img.width=MaxHeight*WidthHeight;
}
}
function CheckImg(img)
{
var message="";
var MaxWidth=1;//设置图片宽度界限
var MaxHeight=1;//设置图片高度界限
if(img.readyState!="complete"){
return false;//确保图片完全加载
}
if(img.offsetHeight>MaxHeight) message+="\r高度超额："+img.offsetHeight;
if(img.offsetWidth>MaxWidth) message+="\r宽度超额："+img.offsetWidth;
if(message!="") alert(message);
}
</script>
</HEAD>
<BODY>
<img src="/static/imghw/default1.png" data-src="http://img.jbxue.com/attachment/portal/jcwcj/2005-12/10/05121010110262394.gif" class="lazy" border=0 id="img1" onload="CheckImg(this);" alt="Detailed explanation of how to obtain picture width and height information in php" >
<br>
<input id=inp type="file" onpropertychange="img1.src="http://img.jbxue.com/attachment/portal">
</BODY>
</HTML> Copy after login |
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