ant - 如何在ant中访问属性内的属性

Question

大家好，请看一下这段代码

在我的属性文件中，我有
win-x86.pc-shared-location=E:\Ant_Scripts

现在下面我想打电话 PrintInstallerName_build来自我的 build.xml，而为 PrintInstallerName_build在 test.xml 中。在 build.xml 文件中，${platform.id} has value=win-x86在调用目标和被调用目标 param1 中也有 value=win-x86

    <target name="PrintInstallerName" >
    <echo>PlatForm.Id====>${platform.id}</echo>
    <ant antfile="test.xml" target="PrintInstallerName_build">
        <property name="param1" value="${platform.id}"/>
    </ant>


<target name="PrintInstallerName_build" >
       <echo>${param1.pc-shared-location}</echo><!--${param1.pc-shared-location}-->
        <echo>${param1}.pc-shared-location}</echo><!--win-x86.pc-shared-location-->
    <echo>${win-x86.pc-shared-location}</echo><!--E:\\Ant_Scripts-->
</target>

正如你所看到的，只有最后一条语句给出了正确的输出，但它是硬编码的，我想使用 param1 并且输出应该是 E:\\Ant_Scripts我尝试使用 $ 和 @ 但没有任何效果，可能是我在某处做错了有人可以帮忙吗，我很震惊，明天就是它的 DOD。

Answer 1

请参见 Properties 中的大括号嵌套Ant 手册的页面。

In its default configuration Ant will not try to balance braces in property expansions, it will only consume the text up to the first closing brace when creating a property name. I.e. when expanding something like ${a${b}} it will be translated into two parts:

the expansion of property a${b - likely nothing useful.
the literal text } resulting from the second closing brace

This means you can't use easily expand properties whose names are given by properties, but there are some workarounds for older versions of Ant. With Ant 1.8.0 and the the props Antlib you can configure Ant to use the NestedPropertyExpander defined there if you need such a feature.