php正则提取html图片(img)src地址与任意属性

简单版

<?php  
header("Content-Type: text/html;charset=utf-8");  
  
$str = '<div class="ui-block-a" align="center">  
        <a href="online-39.html">![](http://www.smsyun.com/uploads/image/20140620/2014052010425.jpg)  
        <h3>2014年</h3></a>  
      </div>';  
  
$imgpreg = "/<img (.*?) src=\"(.+?)\".*?>/";  
preg_match($imgpreg,$str,$img);  
$mycount=count($img)-1;  
 $imgval = $iim[$mycount];  
if(!empty($imgval)){  
    echo $imgval;  
}else{  
    echo 'no';  
}  
?>  

详细版

<?php  
/*PHP正则提取图片img标记中的任意属性*/  
$str = '<center>![](/uploads/images/20100516000.jpg)<br />PHP正则提取或更改图片img标记中的任意属性</center>';  
  
//1、取整个图片代码  
preg_match('/<\s*img\s+[^>]*?src\s*=\s*(\'|\")(.*?)\\1[^>]*?\/?\s*>/i',$str,$match);  
echo $match[0];  
  
//2、取width  
preg_match('/<img.+(width=\"?\d*\"?).+>/i',$str,$match);  
echo $match[1];  
  
//3、取height  
preg_match('/<img.+(height=\"?\d*\"?).+>/i',$str,$match);  
echo $match[1];  
  
//4、取src  
preg_match('/<img.+src=\"?(.+\.(jpg|gif|bmp|bnp|png))\"?.+>/i',$str,$match);  
echo $match[1];  
  
/*PHP正则替换图片img标记中的任意属性*/  
//1、将src="/uploads/images/20100516000.jpg"替换为src="/uploads/uc/images/20100516000.jpg")  
print preg_replace('/(<img.+src=\"?.+)(images\/)(.+\.(jpg|gif|bmp|bnp|png)\"?.+>)/i',"\${1}uc/images/\${3}",$str);  
echo "<hr/>";  
  
//2、将src="/uploads/images/20100516000.jpg"替换为src="/uploads/uc/images/20100516000.jpg",并省去宽和高  
print preg_replace('/(<img).+(src=\"?.+)images\/(.+\.(jpg|gif|bmp|bnp|png)\"?).+>/i',"\${1} \${2}uc/images/\${3}>",$str);  
?>