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                        /前端開發(fā)
                        
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                        /JavaScript進階篇

請問哪里錯了

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? <div><b id="oldnode">JavaScript</b>是一個很常用的技術，為網頁添加動態(tài)效果。</div>
? <a href="javascript:replaceMessage()"> 將加粗改為斜體</a>
?
??? <script type="text/javascript">
????? function replaceMessage(){
????????? if(document.getElementsByTagName("div").childNodes.nodeName=='b'){
???????????? var newnode = document.createElement("i");
???????????? var newnodeText = document.createTextNode("JavaScipt");
???????????? newnode.appendChild(newnodeText);
???????????? var oldNode = document.getElementById("oldnode");
???????????? oldNode.parentNode.replaceChild(newnode,oldNode);}
????????? else{
????????????? var oldNode = document.createElement("b");
????????????? var oldNodeText = document.createTextNode("JavaScipt");
????????????? oldNode.appendChild(oldNodeText);
????????????? newnode.setAttribute("id","newnode");
????????????? var newnode = document.getElementById("newnode");
????????????? newnode.parentNode.replaceChild(oldNode,newnode);}
???????? }
?????? }???
? </script>
?
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