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    copied!<p>If you want the property tree to reflect the hierarchy, then it requires writing a custom parser. Per the INI parser <a href="http://www.boost.org/doc/libs/1_53_0/doc/html/boost_propertytree/parsers.html#boost_propertytree.parsers.ini_parser" rel="nofollow">documentation</a>:</p> <blockquote> <p>INI is a simple key-value format with a single level of sectioning. [...] not all property trees can be serialized as INI files.</p> </blockquote> <p>Because of the single level sectioning, <code>my.section.subsection1</code> must be treated as a key, rather than a hierarchy path. For example, the <code>my.section.subsection1.someProp1</code> path could be broken down into:</p> <pre class="lang-none prettyprint-override"><code> key separator value .----------^---------. ^ .---^---. |my.section.subsection1|.|someProp1| </code></pre> <p>Because "." is part of the key, the <a href="http://www.boost.org/doc/libs/1_53_0/doc/html/boost/property_tree/string_path.html" rel="nofollow"><code>boost::property_tree::string_path</code></a> type must be explicitly instantiated with a different separator. It is available as a <code>path_type</code> typedef on <code>ptree</code>. In this case, I have opted to use "/":</p> <pre><code> ptree::path_type("my.section.subsection1/someProp1", '/') </code></pre> <hr> <p>With example.ini containing:</p> <pre class="lang-none prettyprint-override"><code>[my.section.subsection1] someProp1=0 [my.section.subsection2] anotherProp=1 </code></pre> <p>The following program:</p> <pre class="lang-cpp prettyprint-override"><code>#include &lt;iostream&gt; #include &lt;boost/property_tree/ptree.hpp&gt; #include &lt;boost/property_tree/ini_parser.hpp&gt; int main() { namespace pt = boost::property_tree; pt::ptree propTree; read_ini("example.ini", propTree); boost::optional&lt;uint32_t&gt; someProp1 = propTree.get_optional&lt;uint32_t&gt;( pt::ptree::path_type( "my.section.subsection1/someProp1", '/')); boost::optional&lt;uint32_t&gt; anotherProp = propTree.get_optional&lt;uint32_t&gt;( pt::ptree::path_type( "my.section.subsection2/anotherProp", '/')); std::cout &lt;&lt; "someProp1 = " &lt;&lt; *someProp1 &lt;&lt; "\nanotherProp = " &lt;&lt; *anotherProp &lt;&lt; std::endl; } </code></pre> <p>Produces the following output:</p> <pre class="lang-none prettyprint-override"><code>someProp1 = 0 anotherProp = 1 </code></pre>
 

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