php如何獲取豆瓣電影評分？

<span class="branch">
    {if:"{playpage:douban}"==""}
    <span class="font-size-12">暫無評分 </span>     
    {elseif:{playpage:douban} == 0}
    <span class="font-size-12">暫無評分 </span>
    {else}{playpage:douban}
    {end if} 
</span>


<script type="text/javascript">
    var str = "{playpage:douban}%" 
    document.getElementById("score").style.width = (str.replace(".", ""))
</script>

以上代碼，為什么獲取不到豆瓣評分？哪個(gè)地方有問題，求解？！