JavaScript实现添加、查找、删除元素

代码很简单，这里就不多废话了。

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>测试文件</title>
<style>
.reply {
  width: 500px;
  height: 100%;
  overflow: hidden;
  background-color:#CCC;
  margin-top: 10px;
}
.infoArea {
  width: 380px;
  height: 100%;
  overflow: hidden;
}
.words {
  width: 380px;
  height: auto;
  margin: 5px 0px;
  float: left;
  font-size: 14px;
}
.time {
  margin-left: 10px;
  margin-bottom: 3px;
  width: 150px;
  height: 20px;
  line-height: 20px;
  float: left;
  font-family: 楷体;
  font-size: 14px;
  color: #999;
}
.replyButton {
  width: 60px;
  height: 20px;
  float: left;
  margin-bottom: 10px;
}
.replyButton input {
  font-size: 12px;
}
#cancelButton {
  visibility: hidden;
}
</style>
</head>
 
<body>
<div class="reply">
 <div class="infoArea">
  <div class="words"><a href="">中央情报局</a>:中央情报局</div>
  <div class="time">2014年5月4日21:56</div>
  <div class="replyButton">
   <input type="button" id="submitButton" value="回复" onClick="showReplyArea(this)" />
  </div>
  <div class="replyButton">
   <input type="button" id="cancelButton" value="取消" onClick="hideReplyArea(this)" />
  </div>
 </div>
</div>
<script>
//显示文本框的函数
function showReplyArea(src)
{
  inputText = document.createElement("DIV");
  inputText.className = "inputText";
  inputText.style.width = '100%';
  inputText.style.height = '75px';
  inputText.style.margin = '3px 0';
  inputText.style.cssFloat = 'left';
   
  var grandfather = src.parentNode.parentNode.parentNode;
  grandfather.appendChild(inputText);
   
  form1 = document.createElement("FORM");
  form1.action = "";
  form1.method = "post";
  inputText.appendChild(form1);
   
  inputTextArea = document.createElement("TEXTAREA");
  inputTextArea.style.width = '380px';
  inputTextArea.style.height = '40px';
  inputTextArea.style.marginLeft = '60px';
  inputTextArea.style.marginTop = '3px';
  inputTextArea.style.cssFloat = 'left';
  inputTextArea.style.resize = 'none';
   
  textSubmit = document.createElement("INPUT");
  textSubmit.type = 'submit';
  textSubmit.value = '提交';
  textSubmit.style.marginLeft = '80px';
  textSubmit.style.cssFloat = 'left';
   
  form1.appendChild(inputTextArea);
  form1.appendChild(textSubmit);
   
  cancelButton = grandfather.getElementsByTagName("INPUT").item(1);
  cancelButton.style.visibility = 'visible';
  submitButton = src;
  submitButton.disabled = true;
}
//隐藏文本框的函数
function hideReplyArea(src)
{
  var grandfather = src.parentNode.parentNode.parentNode;
  var inputText = grandfather.getElementsByClassName('inputText').item(0);
  grandfather.removeChild(inputText);
   
  cancelButton = src;
  cancelButton.style.visibility = 'hidden';
  submitButton = grandfather.getElementsByTagName("INPUT").item(0);
  submitButton.disabled = false;
}
 
//下面为调试时测试用函数，做完后就没用了，但也是很经典的一段代码，就留在这里了。
function showNode()
{
  var i = 4;
  submitButton = document.getElementById('submitButton');
  i = submitButton.parentNode.parentNode.getElementsByTagName("INPUT").item(1).value;
  alert(i);
}
</script>
</body>
</html>

示例二：

window.onload = function() {
  var gaga = document.getElementById("gaga");
  addClass(gaga, "gaga1") addClass(gaga, "gaxx");
  removeClass(gaga, "gaga1") removeClass(gaga, "gaga") function hasClass(elements, cName) {
    return !! elements.className.match(new RegExp("(\\s|^)" + cName + "(\\s|$)")); // ( \\s|^ ) 判断前面是否有空格 （\\s | $ ）判断后面是否有空格 两个感叹号为转换为布尔值 以方便做判断 
  };
  function addClass(elements, cName) {
    if (!hasClass(elements, cName)) {
      elements.className += " " + cName;
    };
  };
  function removeClass(elements, cName) {
    if (hasClass(elements, cName)) {
      elements.className = elements.className.replace(new RegExp("(\\s|^)" + cName + "(\\s|$)"), " "); // replace方法是替换 
    };
  };
};

以上所述就是本文的全部内容了，希望大家能够喜欢。