XPath函数——字符串函数(转载)

时间:2021-09-26 01:37:47

本文是转载的,原文网址:http://www.cnblogs.com/zhaozhan/archive/2010/01/17/1650242.html

字符串函数主要用来处理字符串。字符串函数主要包括以下:concat(),contains(),normalize-space(),substing(),substring-before(),subsring-after(),translate().

1、concat()

concat()函数用于串连多个字符串。

简单示例:

xml:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <root>
    <e id="1">st</e>
    <e id="2">nd</e>
    <e id="3">rd</e>
    </root>

xslt:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="text" version="1.0" encoding="gb2312" indent="yes"/>
    <xsl:template match="/root">
    <xsl:for-each select="e">
    <xsl:value-of select="concat(@id,.,' ')"/>
    </xsl:for-each>
    </xsl:template>
    </xsl:stylesheet>

结果:

  1. 1st
    2nd
    3rd

2、contains()

contains(str1,str2)函数用来判断str2是否是第一个字符串的一部分。

简单示例:

xml:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <books>
    <book>XML</book>
    <book>XSLT</book>
    <book>XPath</book>
    <book>C#</book>
    </books>

xslt:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="xml" version="1.0" encoding="gb2312" indent="yes"/>
    <xsl:template match="/books">
    <books>
    <xsl:for-each select="book">
    <xsl:if test="contains(.,'X')">
    <xsl:copy>
    <xsl:value-of select="."/>
    </xsl:copy>
    </xsl:if>
    </xsl:for-each>
    </books>
    </xsl:template>
    </xsl:stylesheet>

结果:

  1. <?xml version="1.0" encoding="gb2312"?>
  2. <books>
  3.     <book>XML</book>
    <book>XSLT</book>
    <book>XPath</book>
    </books>

3、normalize-space()

normalize-space()用来将一个字符串的头部和尾部的空白字符删除,如果字符串中间含有多个连续的空白字符,将用一个空格来代替。

简单示例:

xml:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <article>
    <title> When The Wind Blows</title>
    <paragraph>
    When you have get ready for everything ,you could
    Sleep though the wind blows
    </paragraph>
    <paragraph>
    That means you should do your best on your work and fear
    nothing
    </paragraph>
    </article>

xslt:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="xml" version="1.0" encoding="gb2312" indent="yes"/>
    <xsl:template match="/books">
    <xsl:apply-templates select="article"/>
    </xsl:template>
    <xsl:template match="article">
    <xsl:copy>
    <xsl:apply-templates select="*"/>
    </xsl:copy>
    </xsl:template>
    <xsl:template match="*">
    <xsl:copy>
    <xsl:value-of select="normalize-space()"/>
    </xsl:copy>
    </xsl:template>
    </xsl:stylesheet>

结果:

  1. <?xml version="1.0" encoding="gb2312"?>
    <article>
    <title>When The Wind Blows</title>
    <paragraph>When you have get ready for everything ,you could Sleep though the wind blows</paragraph>
    <paragraph>That means you should do your best on your work and fear nothing</paragraph>
    </article>

4、starts-with()

start-with(string,startr)函数用来判断string是否以startstr开头。

简单示例:

xml:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <books>
    <book>XML</book>
    <book>XSLT</book>
    <book>XPath</book>
    <book>C#</book>
    </books>

xslt:

显示行号 复制代码 ?
  1. <?xml version="1.0" encoding="UTF-8"?>
    <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="xml" version="1.0" encoding="gb2312" indent="yes"/>
    <xsl:template match="/books">
    <xsl:copy>
    <xsl:for-each select="book">
    <xsl:if test="starts-with(.,'X')">
    <xsl:copy-of select="."/>
    </xsl:if>
    </xsl:for-each>
    </xsl:copy>
    </xsl:template>
    </xsl:stylesheet>

结果:

  1. <?xml version="1.0" encoding="gb2312"?>
  2. <books>
  3.     <book>XML</book>
    <book>XSLT</book>
    <book>XPath</book>
    </books>

5、string-length()

string-length(string)函数用来返回参数string的长度,如果参数string为缺省,将返回上下文节点的字符串长度。

6、substring()

substring(string,number,length)函数用来截取字符串。参数string用于指定要截取的字符串;参数number用于指定开始位置;参数length用于指定截取字符串的长度。如果缺少length参数将从开始位置number一直到截取字符串的长度

简单示例:

xml:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <root>
    <text>123456789ABCDEF</text>
    </root>

xslt:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="text" version="1.0" encoding="gb2312" indent="yes"/>
    <xsl:template match="/root">
    <xsl:value-of select="substring(text,1,5)"/>
    <xsl:text> </xsl:text>
    <xsl:value-of select="substring(text,1)"/>
    <xsl:text> </xsl:text>
    <xsl:value-of select="substring(text,1,string-length(text))"/>
    </xsl:template>
    </xsl:stylesheet>

结果:

  1. 12345
    123456789ABCDEF
    123456789ABCDEF

7、substring-before()

substring-before(str1,str2)函数用于返回字符串str1中位于字符串str2之前的部分。

简单示例:

xml:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <datetime>
    <date>2010-01-17</date>
    <time>22:49:30</time>
    </datetime>

xslt:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="text" version="1.0" encoding="gb2312" indent="yes"/>
    <xsl:template match="/datetime">
    <xsl:apply-templates select="*"/>
    </xsl:template>
    <xsl:template match="date">
    <xsl:value-of select="concat(substring-before(.,'-'),'年')"/>
    </xsl:template>
    <xsl:template match="time">
    <xsl:value-of select="concat(substring-before(.,':'),'时')"/>
    </xsl:template>
    </xsl:stylesheet>

结果:

  1. 2010年22时

8、substring-after()

substring-after(str1,str2)函数跟substring-before类似,substring-after0返回字符串str1中位于字符串str2之后的部分。

简单示例:

xml:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <dir>
    <file>a.txt</file>
    <file>t.xml</file>
    <file>t.xslt</file>
    </dir>

xslt:

  1. <?xml version="1.0" encoding="UTF-8"?>
    <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="xml" version="1.0" encoding="gb2312" indent="yes"/>
    <xsl:template match="/dir">
    <extends>
    <xsl:for-each select="file">
    <extend>
    <xsl:value-of select="substring-after(.,'.')"/>
    </extend>
    </xsl:for-each>
    </extends>
    </xsl:template>
    </xsl:stylesheet>

结果:

  1. <?xml version="1.0" encoding="gb2312"?>
    <extends>
    <extend>txt</extend>
    <extend>xml</extend>
    <extend>xslt</extend>
    </extends>

9、translate()

translate(string,replaced_txt,replacement_txt)函数用来替换字符串,替换string中的所有replaced_txt为replacement_txt.