Ant - If Else 参数 - 菜鸟教程

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。

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。

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>

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>