我看过这里的各种建议，但没有一个能真正解决我的问题。 由于我的 XML 的来源，我可以接收以下三种格式的日期；

04-04-2014(DD-MM-YYYY)
04-Apr-2014(DD-MMM-YYYY)
2014-04-04(YYYY-MM-DD)

我想要一个函数或简单的命令来将所有这些(除了第三个，但能够识别第三个是正确的)更改为 YYYY-MM-DD

我目前对何时/何时/何时执行此操作有一个冗长的啰嗦，但必须有更简单的方法。我当前的 XSLT 执行以下操作；

<xsl:choose>
    <xsl:when test="contains(date, 'Jan')">
        <xsl:value-of select="concat(substring(date,6),'-01-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="contains(date, 'Feb')">
        <xsl:value-of select="concat(substring(date,6),'-02-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="contains(date, 'Mar')">
        <xsl:value-of select="concat(substring(date,6),'-03-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="contains(date, 'Apr')">
        <xsl:value-of select="concat(substring(date,6),'-04-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="contains(date, 'May')">
        <xsl:value-of select="concat(substring(date,6),'-05-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="contains(date, 'Jun')">
        <xsl:value-of select="concat(substring(date,6),'-06-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="contains(date, 'Jul')">
        <xsl:value-of select="concat(substring(date,6),'-07-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="contains(date, 'Aug')">
        <xsl:value-of select="concat(substring(date,6),'-08-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="contains(date, 'Sep')">
        <xsl:value-of select="concat(substring(date,6),'-09-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="contains(date, 'Oct')">
        <xsl:value-of select="concat(substring(date,6),'-10-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="contains(date, 'Nov')">
        <xsl:value-of select="concat(substring(date,6),'-11-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="contains(date, 'Dec')">
        <xsl:value-of select="concat(substring(date,6),'-12-',substring(date,1,2))" />
    </xsl:when>
    <xsl:when test="string-length($dateStart) = 2">
        <xsl:value-of select="concat(substring(date,7),'-',substring(date,4,2),'-',substring(date,1,2))" />
    </xsl:when>
    <xsl:otherwise>
        <xsl:value-of select="date"/>
    </xsl:otherwise>
</xsl:choose>

因此这将检查日期是否包含任何月份，如 JAN、Feb 等，如果没有，则检查第一个数字是否为 - 是 2 个字符 (DD) 和格式，否则它假定它是 YYYY-MM -DD already 并按原样输出。

我试过了 - <xsl:value-of select = "format-dateTime(date, '[Y0001]-[MN]-[D01]')"/> 但这提示日期年份不够长(因为日期被视为日期时间，格式应为 YYYY-MM-DD

感谢下面的 Ian roberts Answer，我创建了下面的内容来处理更多场景并将输出组合在一起；

<xsl:variable name="months" select="('Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec')" />
<xsl:analyze-string select="date" flags="x"
       regex="^(
            (\d\d)-(\d\d)-(\d\d\d\d)
          | (\d\d)-([A-Za-z]{{3}})-(\d\d\d\d)
          | (\d\d\d\d)-(\d\d)-(\d\d)
          | (\d\d\d\d)-([A-Za-z]{{3}})-(\d\d)
          | (\d\d)([A-Za-z]{{3}})(\d\d\d\d)
          | (\d\d\d\d)([A-Za-z]{{3}})(\d\d))$">
        <xsl:matching-substring>
            <xsl:value-of select="if (regex-group(4)) then concat(regex-group(4),'-',regex-group(3),'-',regex-group(2)) else ''"/>
            <xsl:value-of select="if (regex-group(7)) then concat(regex-group(7),'-',format-number(index-of($months, regex-group(6)), '00'),'-',regex-group(5)) else ''"/>
            <xsl:value-of select="if (regex-group(8)) then concat(regex-group(8),'-',regex-group(9),'-',regex-group(10)) else ''"/>
            <xsl:value-of select="if (regex-group(11)) then concat(regex-group(11),'-',format-number(index-of($months, regex-group(12)), '00'),'-',regex-group(13)) else ''"/>
            <xsl:value-of select="if (regex-group(16)) then concat(regex-group(16),'-',format-number(index-of($months, regex-group(15)), '00'),'-',regex-group(14)) else ''"/>
            <xsl:value-of select="if (regex-group(17)) then concat(regex-group(17),'-',format-number(index-of($months, regex-group(18)), '00'),'-',regex-group(19)) else ''"/>
        </xsl:matching-substring>
    </xsl:analyze-string>

最佳答案

即使在 XSLT 1.0 中，一旦您关注不同格式的结构而不是它们的内容，问题就会变得相当微不足道:

<xsl:template name="normalize-datestring">
<xsl:param name="datestring"/>
        <xsl:choose>
            <xsl:when test="string-length(substring-before($datestring, '-')) = 4">
            <!-- this is YYYY-MM-DD; copy as is -->
                <xsl:value-of select="$datestring" />
            </xsl:when>
            <xsl:when test="string-length($datestring) = 10">
            <!-- this is DD-MM-YYYY; reorder -->
                <xsl:value-of select="substring($datestring, 7, 4)" />
                <xsl:text>-</xsl:text>
                <xsl:value-of select="substring($datestring, 4, 2)" />
                <xsl:text>-</xsl:text>
                <xsl:value-of select="substring($datestring, 1, 2)" />
            </xsl:when>
            <xsl:otherwise>
            <!-- this is DD-MMM-YYYY; reorder and calculate month number-->
                <xsl:value-of select="substring($datestring, 8, 4)" />
                <xsl:text>-</xsl:text>
                <xsl:variable name="mmm" select="substring($datestring, 4, 3)" />
                <xsl:variable name="m" select="string-length(substring-before('JanFebMarAprMayJunJulAugSepOctNovDec', $mmm)) div 3 + 1" />
                <xsl:value-of select="format-number($m, '00')" />
                <xsl:text>-</xsl:text>
                <xsl:value-of select="substring($datestring, 1, 2)" />
            </xsl:otherwise>
        </xsl:choose>
</xsl:template>

关于xml - XSLT 日期格式，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/22868423/