📄 xpath_getelembytext.htm
字号:
<HTML>
<HEAD>
<META http-equiv="Content-Type" content="text/html; charset=UTF-8">
<TITLE>Finding Elements by Content in a DOM Document Using XPath (Java Developers Almanac Example)
</TITLE>
<META CONTENT="Patrick Chan" NAME="AUTHOR">
<META CONTENT="Code Examples from The Java Developers Almanac 1.4" NAME="DESCRIPTION">
<META CONTENT="Addison-Wesley/Patrick Chan" NAME="OWNER">
<META CONTENT="3/20/02" NAME="revision">
<META CONTENT="no-cache" HTTP-EQUIV="Pragma">
<LINK href="/almanac.css" media="screen" type="text/css" rel="stylesheet">
</HEAD>
<BODY>
<TABLE CELLSPACING="0" CELLPADDING="0" BORDER="0">
<TR>
<TD></TD>
</TR>
</TABLE>
<br>
<TABLE CELLSPACING="0" CELLPADDING="0" BORDER="0">
<TR>
<TD></TD>
</TR>
<TR>
<TD rowspan="3"><A HREF="/?l=ex"><IMG BORDER="0" ALIGN="BOTTOM" HSPACE="10" SRC="/egs/almanac14a.jpg"></A></TD><TD VALIGN="top">
<h1>The Java Developers Almanac 1.4</h1>
<br>
Order this book from <a href="/cgi-bin/scripts/redirect.pl?l=ex&url=http://www.amazon.com/exec/obidos/ASIN/0201752808/xeo">Amazon</a>.
</TD>
</TR>
<TR>
<TD align="right" valign="bottom">
<FORM method="get" action="/cgi-bin/search/find.pl">
<INPUT size="25" name="words" type="text"><INPUT value="Search" type="submit">
</FORM>
</TD>
</TR>
</TABLE>
<HR color="#6666cc">
<TABLE CELLSPACING="0" CELLPADDING="0" BORDER="0">
<TR>
<TD valign="top"><script type="text/javascript">
<!--
google_ad_client = "pub-6001183370374757";
google_ad_width = 120;
google_ad_height = 600;
google_ad_format = "120x600_as";
google_ad_channel = "4777242811";
google_ad_type = "text_image";
google_color_border = "FFFFFF";
google_color_bg = "FFFFFF";
google_color_link = "6666CC";
google_color_url = "6666CC";
google_color_text = "000000";
//--></script><script src="http://pagead2.googlesyndication.com/pagead/show_ads.js" type="text/javascript"></script></TD><TD> </TD><TD valign="top">
<DIV ALIGN="LEFT">
<A HREF="/">Home</A>
>
<A HREF="../index.html">List of Packages</A>
>
<A HREF="../org.w3c.dom/pkg.html">org.w3c.dom</A><font color="#666666" class="xsmall-font">
[30 examples]
</font>
>
<B><A HREF="../org.w3c.dom/pkg.html#XPath">XPath</A></B><font color="#666666" class="xsmall-font">
[5 examples]
</font>
</DIV><P>
<h3>e1076. Finding Elements by Content in a DOM Document Using XPath</h3>
XPath is an expression language for selecting nodes in an XML file.
See <a href="../org.w3c.dom/xpath_GetAbsElem.html" class="eglink"><b>e1074</b> Finding Elements by Absolute Location in a DOM Document Using XPath</a> for common XPath
expression for selecting elements. This example adds to those
examples by demonstrating the ability to select elements based on their
content.
<P> In an element such as <code><A>cat</A></code>, the content is simply
<code>"cat"</code>. However, in the case of an element that contains other
elements, the content is the concatenation of the content of all
subelements. For example, in the XML fragment
<code><A>cat<B>,<C>dog,</C>and</B>rat</A></code>,
the content of <code>A</code> is <code>"cat,dog,andrat"</code>.
<P> This example demonstrates some common uses of expressions that
use element content; for more information on XPath, see the
specification at <a href="http://www.w3c.org/TR/xpath">http://www.w3c.org/TR/xpath</a>. In the example,
the result of an XPath expression is shown next to the expression; the
numbers are ids of elements in the sample file shown at the end of the
example.
<pre> // Get all elements that equal the string cat
String xpath = "//*[.='cat']"; // 2 6
// Get all elements that equal the string dog
xpath = "//*[.='dog']"; // (none)
// Note that element #3 does not match because its
// content is <code>" dog "</code> rather than <code>"dog"</code>
// Get all elements that contain the string cat
xpath = "//*[contains(.,'cat')]"; // 1 2 4 5 6
// Get all elem3 elements that contain the string cat
xpath = "//elem3[contains(.,'cat')]"; // 6
// Get all elements that contain the string cat,
// ignoring the contents of any subelements
xpath = "//*[contains(child::text(),'cat')]"; // 2 4 6
// Get all elements without subelements and whose contents contains the string cat
xpath = "//*[count(*)=0 and contains(.,'cat')]"; // 2 6
</pre>
XPath 1.0 does not support case-insensitive matches. However,
a simple case-insensitive match can be done using the <code>translate()</code>
function, which converts a string by mapping one character into another:
<pre> // Get all elements that contain the string cat, ignoring case
xpath = "//*[contains(translate(.,'abcdefghijklmnopqrstuvwxyz',"
+ " 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'),'CAT')]";
// 1 2 4 5 6 7
</pre>
To execute an XPath expression, see
<a href="../org.w3c.dom/xpath_GetAbsElem.html" class="eglink"><b>e1074</b> Finding Elements by Absolute Location in a DOM Document Using XPath</a>. Here is the sample XML file
used in the example:
<pre> <?xml version="1.0" encoding="UTF-8"?>
<root id="1">
<elem1 id="2">cat</elem1>
<elem1 id="3"> dog </elem1>
<elem1 id="4">
cat
<elem2 id="5">
<elem3 id="6">cat</elem3>
</elem2>
dog
</elem1>
<elem1 id="7">Cat</elem1>
</root>
</pre>
<P><table width="600" CELLSPACING="0" CELLPADDING="2" BORDER="0">
<tr>
<td bgcolor="#6666cc" align="center"><font color="#ffffff">
<b>Related Examples</b></font></td>
</tr>
</table>
e1074. <a class="eglink" href="xpath_GetAbsElem.html?l=rel">
Finding Elements by Absolute Location in a DOM Document Using XPath
</a>
<br>
e1075. <a class="eglink" href="xpath_GetChildElem.html?l=rel">
Selecting from a Set of Child Elements in a DOM Document Using XPath
</a>
<br>
e1077. <a class="eglink" href="xpath_GetElemById.html?l=rel">
Finding Elements by Id in a DOM Document Using XPath
</a>
<br>
e1078. <a class="eglink" href="xpath_GetElemByAttr.html?l=rel">
Finding Elements by Attributes in a DOM Document Using XPath
</a>
<br>
<table width="600" CELLSPACING="0" CELLPADDING="2" BORDER="0">
<tr>
<td align="left">
<br>
See also:
<a class="eglink" href="/egs/org.w3c.dom/pkg.html?l=rel#Adding%20and%20Removing%20Nodes">
Adding and Removing Nodes
</a>
<a class="eglink" href="/egs/org.w3c.dom/pkg.html?l=rel#Element%20Attributes">
Element Attributes
</a>
<a class="eglink" href="/egs/org.w3c.dom/pkg.html?l=rel#Elements">
Elements
</a>
<a class="eglink" href="/egs/org.w3c.dom/pkg.html?l=rel#Getting%20Nodes">
Getting Nodes
</a>
<a class="eglink" href="/egs/org.w3c.dom/pkg.html?l=rel#Text%20Nodes">
Text Nodes
</a>
</td>
</tr>
</table>
<br>
<br>
<FONT class="xsmall-font">
© 2002 Addison-Wesley.
</FONT></TD><TD> </TD><TD valign="top"><A href="http://compositesw.com/devzone?ref=javaalmanac"><IMG alt="Click Here" height="600" width="120" border="0" src="/csw_oad_120x600_final.gif"></A></TD>
</TR>
</TABLE>
</BODY>
<HEAD>
<META http-equiv="Content-Type" content="text/html; charset=UTF-8">
<META CONTENT="NO-CACHE" HTTP-EQUIV="PRAGMA">
</HEAD>
</HTML>
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -