Ant - If Else 参数

• 

  简述

  Ant 允许根据传递的条件运行目标。我们可以用if声明或unless陈述。
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  句法

  
  
  <target name="copy" if="copyFile">
  
     <echo>Files are copied.</echo>
  
  </target>
  
  <target name="move" unless="copyFile">
  
     <echo>Files are moved.</echo>
  
  </target>
  
  

  我们将使用 -Dproperty 将像 copyFile 这样的变量传递给构建任务。变量是要定义的，变量的值在这里无关紧要。
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  例子

  使用以下内容创建 build.xml -

  
  
  <?xml version="1.0"?>
  
  <project name="sample" basedir="." default="copy">
  
     <target name="copy" if="copyFile">
  
        <echo>Files are copied.</echo>
  
     </target>
  
     <target name="move" unless="copyFile">
  
        <echo>Files are moved.</echo>
  
     </target>
  
  </project>
  
  

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  输出

  在上述构建文件上运行 Ant 会产生以下输出 -

  
  
  F:\jc2182\ant>ant -DcopyFile=true
  
  Buildfile: F:\jc2182\ant\build.xml
  
  
  
  copy:
  
     [echo] Files are copied.
  
  
  
  BUILD SUCCESSFUL
  
  Total time: 0 seconds
  
  
  
  F:\jc2182\ant>ant move
  
  Buildfile: F:\jc2182\ant\build.xml
  
  
  
  move:
  
     [echo] Files are moved.
  
  
  
  BUILD SUCCESSFUL
  
  Total time: 0 seconds
  
  
  
  F:\jc2182\ant>ant move -DcopyFile=true
  
  Buildfile: F:\jc2182\ant\build.xml
  
  
  
  move:
  
  
  
  BUILD SUCCESSFUL
  
  Total time: 0 seconds
  
  
  
  F:\jc2182\ant>ant move -DcopyFile=false
  
  Buildfile: F:\jc2182\ant\build.xml
  
  
  
  move:
  
  
  
  BUILD SUCCESSFUL
  
  Total time: 0 seconds
  
  
  
  F:\jc2182\ant>ant move -DcopyFile=true
  
  Buildfile: F:\jc2182\ant\build.xml
  
  
  
  move:
  
  
  
  BUILD SUCCESSFUL
  
  Total time: 0 seconds
  
  
  
  F:\jc2182\ant>ant move
  
  Buildfile: F:\jc2182\ant\build.xml
  
  
  
  move:
  
     [echo] Files are moved.
  
  
  
  BUILD SUCCESSFUL
  
  Total time: 0 seconds
  
  
  
  F:\jc2182\ant>