相容IE和FF的圖片上傳前預覽js程式碼_javascript技巧

效果圖如下：
 
程式碼如下：

複製程式碼";
}
}
function clacImgZoomParam( maxWidth, maxHeight, width, height ){ var. = {top:0, left:0, width:width, height:height};
if( width>maxWidth || height>maxHeight )
{
rateWidth = width / maxWidth; = height / maxHeight;

if( rateWidth > rateHeight )
{
param.width = maxWidth;
param.height = Math.round(height / rateWidth); else
{
param.width = Math.round(width / rateHeight);
param.height = maxHeight;
}
}

param. round((maxWidth - param.width) / 2);
param.top = Math.round((maxHeight - param.height) / 2);
return param;
}
script>