如何在XSLT中实现if-else语句?

I am trying to implement an if -else statement in XSLT but my code just doesn't parse. Does anyone have any ideas?

我试图在XSLT中实现if -else语句，但我的代码无法解析。有人有什么想法吗?

  <xsl:variable name="CreatedDate" select="@createDate"/>
  <xsl:variable name="IDAppendedDate" select="2012-01-01" />
  <b>date: <xsl:value-of select="$CreatedDate"/></b> 

  <xsl:if test="$CreatedDate > $IDAppendedDate">
    <h2> mooooooooooooo </h2>
  </xsl:if>
  <xsl:else>
    <h2> dooooooooooooo </h2>
  </xsl:else>

4 个解决方案

#1

You have to reimplement it using <xsl:choose> tag:

您必须使用 标记:

       <xsl:choose>
         <xsl:when test="$CreatedDate > $IDAppendedDate">
           <h2> mooooooooooooo </h2>
         </xsl:when>
         <xsl:otherwise>
          <h2> dooooooooooooo </h2>
         </xsl:otherwise>
       </xsl:choose>

#2

If statement is used for checking just one condition quickly. When you have multiple options, use <xsl:choose> as illustrated below:

If语句用于快速检查一个条件。当您有多个选项时，使用 ，如下所示:

   <xsl:choose>
     <xsl:when test="$CreatedDate > $IDAppendedDate">
       <h2>mooooooooooooo</h2>
     </xsl:when>
     <xsl:otherwise>
      <h2>dooooooooooooo</h2>
     </xsl:otherwise>
   </xsl:choose>

Also, you can use multiple <xsl:when> tags to express If .. Else If or Switch patterns as illustrated below:

此外，您可以使用多个 标记表示是否..如果或切换如下所示的模式: 当>

   <xsl:choose>
     <xsl:when test="$CreatedDate > $IDAppendedDate">
       <h2>mooooooooooooo</h2>
     </xsl:when>
     <xsl:when test="$CreatedDate = $IDAppendedDate">
       <h2>booooooooooooo</h2>
     </xsl:when>
     <xsl:otherwise>
      <h2>dooooooooooooo</h2>
     </xsl:otherwise>
   </xsl:choose>

The previous example would be equivalent to the pseudocode below:

前面的例子相当于下面的伪代码:

   if ($CreatedDate > $IDAppendedDate)
   {
       output: <h2>mooooooooooooo</h2>
   }
   else if ($CreatedDate = $IDAppendedDate)
   {
       output: <h2>booooooooooooo</h2>
   }
   else
   {
       output: <h2>dooooooooooooo</h2>
   }

#3

If I may offer some suggestions (two years later but hopefully helpful to future readers):

如果我能提供一些建议(两年后希望对未来的读者有所帮助):

• Factor out the common h2 element.
• 提出共同的h2元素。
• Factor out the common ooooooooooooo text.
• 提出常见的ooooooooooooo文本。
• Be aware of new XPath 2.0 if/then/else construct if using XSLT 2.0.
• 如果使用XSLT 2.0，请注意新的XPath 2.0 if/then/else结构。

XSLT 1.0 Solution ^{_{(also works with XSLT 2.0)}}

<h2>
  <xsl:choose>
    <xsl:when test="$CreatedDate > $IDAppendedDate">m</xsl:when>
    <xsl:otherwise>d</xsl:otherwise>
  </xsl:choose>
  ooooooooooooo
</h2>

XSLT 2.0 Solution

<h2>
   <xsl:value-of select="if ($CreatedDate > $IDAppendedDate) then 'm' else 'd'"/>
   ooooooooooooo
</h2>

#4

The most straight-forward approach is to do a second if-test but with the condition inverted. This technique is shorter, easier on the eyes, and easier to get right than a choose-when-otherwise nested block:

最直接的方法是进行第二次if-test，但条件相反。这种技术更短，更容易看，也更容易得到正确，而不是选择什么时候嵌套的块:

<xsl:variable name="CreatedDate" select="@createDate"/>
     <xsl:variable name="IDAppendedDate" select="2012-01-01" />
     <b>date: <xsl:value-of select="$CreatedDate"/></b> 
     <xsl:if test="$CreatedDate &gt; $IDAppendedDate">
        <h2> mooooooooooooo </h2>
     </xsl:if>
     <xsl:if test="$CreatedDate &lt;= $IDAppendedDate">
        <h2> dooooooooooooo </h2>
     </xsl:if>

Here's a real-world example of the technique being used in the style-sheet for a government website: http://w1.weather.gov/xml/current_obs/latest_ob.xsl

下面是一个在*网站的样式表中使用的技术实例:http://w1.weather.gov/xml/current_obs/latest_ob.xsl。