Integrate user note into the manual

reference/datetime/datetimeinterface/diff.xml

@@ -1,6 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- $Revision$ -->
-<!-- EN-Revision: 02ff7fef5b34cf8f5395180d9d39fb64d9398d00 Maintainer: mowangjuanzi Status: ready -->
+<!-- EN-Revision: dbbcd32d72e4c9af14e9f3b940edbedfb54f965e Maintainer: mowangjuanzi Status: ready -->
+<!-- CREDITS: Luffy -->
 <refentry xml:id="datetime.diff" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
  <refnamediv>
   <refname>DateTimeInterface::diff</refname>
@@ -134,6 +135,31 @@ echo $interval->format("%H:%I:%S (Full days: %a)"), "\n";
    </screen>
   </example>
 
+  <example>
+   <title><methodname>DateTimeInterface::diff</methodname> range</title>
+   <para>
+    该方法返回的值是从 <parameter>$this</parameter> 到达 <parameter>$targetObject</parameter> 
+    所需要的精确时间。因此，将 1 月 1 日与 12 月 31 日进行比较，返回的结果是 364，而不是
+    365 天（对于非闰年）。
+   </para>
+   <programlisting role="php">
+    <![CDATA[
+<?php
+$originalTime = new DateTimeImmutable("2023-01-01 UTC");
+$targedTime = new DateTimeImmutable("2023-12-31 UTC");
+$interval = $originalTime->diff($targedTime);
+echo "Full days: ", $interval->format("%a"), "\n";
+?>
+]]>
+   </programlisting>
+   &example.outputs;
+   <screen>
+    <![CDATA[
+Full days: 364
+]]>
+   </screen>
+  </example>
+
   <example>
    <title><classname>DateTime</classname> 对象比较</title>
    <note>