文档.evaluate没有返回正确的TextNodes XPath

我正在为Android的WebView创建"Highlighter"。我通过以下函数获得HTML中所选范围的XPath表达式

/HTML DIV[1]/身体[1]/[1]/DIV [3]/DIV [1]/DIV [1]/text () [5]

现在我正在通过javascript

中的这个函数评估上面的XPath表达式

var resNode = document.evaluate('/HTML[1]/BODY[1]/DIV[1]/DIV[3]/DIV[1]/DIV[1]/text()[5]',document,null,XPathResult.FIRST_ORDERED_NODE_TYPE ,null);
var startNode = resNode.singleNodeValue;

但是我得到startNode 'null'。

但是，这里有一个有趣的点:

如果我计算这个'/HTML[1]/BODY[1]/DIV[1]/DIV[3]/DIV[1]/DIV[1]' XPath表达式使用相同的函数，它给出适当的节点，即' DIV '。

两个xpath之间的区别是前一个xpath包含textNode，后一个xpath只包含div。

但是同样的事情在桌面浏览器上工作得很好。

示例HTML

<html>
<head>
<script></script>
</head>
<body>
<div id="mainpage" class="highlighter-context">
<div>       Some text here also....... </div>
<div>      Some text here also.........</div>
<div>
  <h1 class="heading"></h1>
  <div class="left_side">
    <ol></ol>
    <h1></h1>
    <div class="text_bio">
    In human beings, height, colour of eyes, complexion, chin, etc. are 
    some recognisable features. A feature that can be recognised is known as 
    character or trait. Human beings reproduce through sexual reproduction. In this                
    process, two individuals one male and another female are involved. Male produces   
    male gamete or sperm and female produces female gamete or ovum. These gametes fuse 
    to form zygote which develops into a new young one which resembles to their parent. 
     During the process of sexual reproduction 
    </div>
  </div>
  <div class="righ_side">
  Some text here also.........
  </div>
  <div class="clr">
         Some text here also.......
  </div>
</div>
</div>
</body>
</html>

XPath:

var selection = window.getSelection(); 
var range = selection.getRangeAt(0); 
var xpJson = '{startXPath :"'+makeXPath(range.startContainer)+      
             '",startOffset:"'+range.startOffset+
             '",endXPath:"'+makeXPath(range.endContainer)+ 
             '",endOffset:"'+range.endOffset+'"}';

生成XPath的函数:

function makeXPath(node, currentPath) {
          currentPath = currentPath || ''; 
          switch (node.nodeType) { 
          case 3:
          case 4:return makeXPath(node.parentNode, 'text()[' + (document.evaluate('preceding-sibling::text()', node, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null).snapshotLength + 1) + ']');
          case 1:return makeXPath(node.parentNode, node.nodeName + '[' + (document.evaluate('preceding-sibling::' + node.nodeName, node, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null).snapshotLength + 1) + ']' + (currentPath ? '/' + currentPath : ''));
          case 9:return '/' + currentPath;default:return '';
    }
}

我不与XML工作，但与HTML在webview。

我尝试使用Rangy序列化和反序列化，但Rangy"序列化"工作正常，而不是"反序列化"。

有什么想法吗，伙计们，出了什么问题?

终于找到了问题的根本原因(尚未解决)

' android webview到底发生了什么?不知何故，android webview正在改变加载的HTML页面的DOM结构。即使DIV不包含任何TEXTNODES，而从DIV中选择文本，我得到TEXTNODE的每一行在DIV中。例如，对于桌面浏览器中的相同的HTML页面，对于相同的文本选择，从webview获得的XPath完全不同于桌面浏览器'

XPath from Desktop Browser:
startXPath /HTML[1]/BODY[1]/DIV[1]/DIV[3]/DIV[1]/DIV[1]/text()[1]
startOffset: 184 
endXPath: /HTML[1]/BODY[1]/DIV[1]/DIV[3]/DIV[1]/DIV[1]/text()[1]
endOffset: 342

Xpath from webview:
startXPath :/HTML[1]/BODY[1]/DIV[1]/DIV[3]/DIV[1]/DIV[1]/text()[3]
startOffset:0 
endXPath:/HTML[1]/BODY[1]/DIV[1]/DIV[3]/DIV[1]/DIV[1]/text()[4]
endOffset:151

在您的示例中，路径/HTML[1]/BODY[1]/DIV[1]/DIV[3]/DIV[1]/DIV[1]/text()[5]选择div元素的第五个文本子节点

<div class="text_bio">
In human beings, height, colour of eyes, complexion, chin, etc. are 
some recognisable features. A feature that can be recognised is known as 
character or trait. Human beings reproduce through sexual reproduction. In this                
process, two individuals one male and another female are involved. Male produces   
male gamete or sperm and female produces female gamete or ovum. These gametes fuse 
to form zygote which develops into a new young one which resembles to their parent. 
 During the process of sexual reproduction 
</div>

div有一个单一的文本子节点，所以我不明白为什么text()[5]应该选择任何东西。

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