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<concept id="GUID-27C933F7-4634-57C8-B3D2-45C5563FECA4" xml:lang="en"><title>How

to use dynamic arrays</title><shortdesc>This document describes how to create templated arrays; that is,

an array of a particular type of object.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>All array classes are templated; the template value defines the type of

object which is to form an element of the array. This is true for arrays of

same length and variable length elements. The following example code constructs

an array of same length elements of type <codeph>TMyClass</codeph> using the

flat array buffer <codeph>CArrayFixFlat&lt;class T&gt;</codeph>. The array has

granularity 16:</p>

<codeblock id="GUID-E59CB1C7-4BFD-574B-97DD-28B82BEDB9BB" xml:space="preserve">CArrayFixFlat&lt;TMyClass&gt; array;

...

array = new (ELeave) CArrayFixFlat<TInt>(16);

...</codeblock>

<p>To construct an array of <codeph>TInt</codeph> values with a <i>granularity</i> of

16, implement code as follows:</p>

<codeblock id="GUID-6B599A36-21EE-50B0-BF18-00C84AEC50A7" xml:space="preserve">CArrayFixFlat&lt;TInt&gt;* array;

...

array = new (ELeave) CArrayFixFlat&lt;TInt&gt;(16);</codeblock>

<p>After construction, the array contains no elements and no memory is allocated

to the array buffer.</p>

<p><codeph>CArrayPtrFlat</codeph> is a specialised array where the elements

are <i>pointers</i> to <codeph>CBase</codeph> derived objects. To construct

an array whose elements are pointers to <codeph>CMyClass</codeph> objects:</p>

<codeblock id="GUID-5F63CDA5-2386-562F-A66D-6963A126314D" xml:space="preserve">CArrayPtrFlat&lt;CMyClass&gt;* array;

...

array = new (ELeave) CArrayPtrFlat&lt;CMyClass&gt;(16);</codeblock>

<p>To construct an array of same length elements of type <codeph>TMyClass</codeph> using <codeph>RArray&lt;class

T&gt;</codeph>:</p>

<codeblock id="GUID-13D94D48-B752-5A31-9CC6-BD94DC2DEE3A" xml:space="preserve">RArray&lt;TMyClass&gt; array; // this is on the stack

...

...                     // add entries etc

...

array.Close();          // called before the array goes out of scope</codeblock>

<p>To construct an array of pointers to <codeph>CMyClass</codeph> objects

using <codeph>RPointerArray&lt;class T&gt;</codeph>:</p>

<codeblock id="GUID-151C2968-19F5-5AA0-BB93-DCBFF023B0DA" xml:space="preserve">RPointerArray&lt;CMyClass&gt; array;  // this is on the stack

...

CMyClass* ptr = new (ELeave) CMyClass;

...

array.Append(ptr);

...

array.ResetAndDestroy();       // called before the array goes

                               // out of scope</codeblock>