png图片(有含有透明)在IE6中为什么不透明了

png-8模式的图片，如果没有渐变的话是透明的，如果有渐变就不透明了。需要js的支持。

 

  
    

   
     
   
     function
   
      correctPNG() 
   
     //
   
      correctly handle PNG transparency in Win IE 5.5 & 6. 
   
     

   
      {
 
   
     var
   
      arVersion 
   
     =
   
      navigator.appVersion.split(
   
     "
   
     MSIE
   
     "
   
     )
 
   
     var
   
      version 
   
     =
   
      parseFloat(arVersion[
   
     1
   
     ])
 
   
     if
   
      ((version 
   
     >=
   
      
   
     5.5
   
     ) 
   
     &&
   
      (document.body.filters)) {
 
   
     for
   
      (
   
     var
   
      j 
   
     =
   
      
   
     0
   
     ; j 
   
     <
   
      document.images.length; j
   
     ++
   
     ) {
 
   
     var
   
      img 
   
     =
   
      document.images[j]
 
   
     var
   
      imgName 
   
     =
   
      img.src.toUpperCase()
 
   
     if
   
      (imgName.substring(imgName.length 
   
     -
   
      
   
     3
   
     , imgName.length) 
   
     ==
   
      
   
     "
   
     PNG
   
     "
   
     ) {
 
   
     var
   
      imgID 
   
     =
   
      (img.id) 
   
     ?
   
      
   
     "
   
     id='
   
     "
   
      
   
     +
   
      img.id 
   
     +
   
      
   
     "
   
     ' 
   
     "
   
      : 
   
     ""
   
     
 
   
     var
   
      imgClass 
   
     =
   
      (img.className) 
   
     ?
   
      
   
     "
   
     class='
   
     "
   
      
   
     +
   
      img.className 
   
     +
   
      
   
     "
   
     ' 
   
     "
   
      : 
   
     ""
   
     
 
   
     var
   
      imgTitle 
   
     =
   
      (img.title) 
   
     ?
   
      
   
     "
   
     title='
   
     "
   
      
   
     +
   
      img.title 
   
     +
   
      
   
     "
   
     ' 
   
     "
   
      : 
   
     "
   
     title='
   
     "
   
      
   
     +
   
      img.alt 
   
     +
   
      
   
     "
   
     ' 
   
     "
   
     
 
   
     var
   
      imgStyle 
   
     =
   
      
   
     "
   
     display:inline-block;
   
     "
   
      
   
     +
   
      img.style.cssText
 
   
     if
   
      (img.align 
   
     ==
   
      
   
     "
   
     left
   
     "
   
     ) imgStyle 
   
     =
   
      
   
     "
   
     float:left;
   
     "
   
      
   
     +
   
      imgStyle
 
   
     if
   
      (img.align 
   
     ==
   
      
   
     "
   
     right
   
     "
   
     ) imgStyle 
   
     =
   
      
   
     "
   
     float:right;
   
     "
   
      
   
     +
   
      imgStyle
 
   
     if
   
      (img.parentElement.href) imgStyle 
   
     =
   
      
   
     "
   
     cursor:hand;
   
     "
   
      
   
     +
   
      imgStyle
 
   
     var
   
      strNewHTML 
   
     =
   
      
   
     "
   
     <span 
   
     "
   
      
   
     +
   
      imgID 
   
     +
   
      imgClass 
   
     +
   
      imgTitle
 
   
     +
   
      
   
     "
   
      style=\
   
     ""
   
      + 
   
     "
   
     width:
   
     "
   
      + img.width + 
   
     "
   
     px; height:
   
     "
   
      + img.height + 
   
     "
   
     px;
   
     "
   
      + imgStyle + 
   
     "
   
     ;
   
     "
   
     
 + 
   
     "
   
     filter:progid:DXImageTransform.Microsoft.AlphaImageLoader
   
     "
   
     
 + 
   
     "
   
     (src
   
     =
   
     \
   
     '
   
     " + img.src + "\
   
     '
   
     , sizingMethod
   
     =
   
     '
   
     scale
   
     '
   
     );\
   
     "
   
     ></span>
   
     "
   
     
 img.outerHTML 
   
     =
   
      strNewHTML
 j 
   
     =
   
      j 
   
     -
   
      
   
     1
   
     
 }
 }
 }
 }
 window.attachEvent(
   
     "
   
     onload
   
     "
   
     , correctPNG);