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    <p>I've demonstrated how to delete items from a dynamic array before:</p> <ul> <li><a href="http://www.cs.wisc.edu/~rkennedy/array-delete" rel="noreferrer">Delphi Q&amp;A: How do I delete an element from an array?</a></li> </ul> <p>In that article, I start with the following code:</p> <pre><code>type TXArray = array of X; procedure DeleteX(var A: TXArray; const Index: Cardinal); var ALength: Cardinal; i: Cardinal; begin ALength := Length(A); Assert(ALength &gt; 0); Assert(Index &lt; ALength); for i := Index + 1 to ALength - 1 do A[i - 1] := A[i]; SetLength(A, ALength - 1); end; </code></pre> <p>You <em>cannot go wrong</em> with that code. Use whatever value for <code>X</code> you want; in your case, replace it with <code>string</code>. If you want to get fancier and use <code>Move</code>, then there's way to do that, too.</p> <pre><code>procedure DeleteX(var A: TXArray; const Index: Cardinal); var ALength: Cardinal; TailElements: Cardinal; begin ALength := Length(A); Assert(ALength &gt; 0); Assert(Index &lt; ALength); Finalize(A[Index]); TailElements := ALength - Index; if TailElements &gt; 0 then Move(A[Index + 1], A[Index], SizeOf(X) * TailElements); Initialize(A[ALength - 1]); SetLength(A, ALength - 1); end; </code></pre> <p>Since <code>X</code> is <code>string</code>, the <code>Finalize</code> call is equivalent to assigning the empty string to that array element. I use <code>Finalize</code> in this code, though, because it will work for <em>all</em> array-element types, even types that include records, interfaces, strings, and other arrays.</p> <p>For inserting, you just shift things the opposite direction:</p> <pre><code>procedure InsertX(var A: TXArray; const Index: Cardinal; const Value: X); var ALength: Cardinal; TailElements: Cardinal; begin ALength := Length(A); Assert(Index &lt;= ALength); SetLength(A, ALength + 1); Finalize(A[ALength]); TailElements := ALength - Index; if TailElements &gt; 0 then begin Move(A[Index], A[Index + 1], SizeOf(X) * TailElements); Initialize(A[Index]); A[Index] := Value; end; </code></pre> <p>Use <code>Finalize</code> when you're about to do something that's outside the bounds of the language, such as using the non-type-safe <code>Move</code> procedure to overwrite a variable of a compiler-managed type. Use <code>Initialize</code> when you're re-entering the defined part of the language. (The language defines what happens when an array grows or shrinks with <code>SetLength</code>, but it doesn't define how to copy or delete strings without using a string-assignment statement.)</p>
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    1. POMove() to Insert/Delete item(s) from a dynamic array of string
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    1. USRob Kennedy
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    1. POMove() to Insert/Delete item(s) from a dynamic array of string
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      1. VTUpMod
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    1. COthank you very much. :-) I will try your snippet code, and will accept this as accepted answer if it succeeds. But I have to go to the office now. :-)
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      1. USPhantom
    2. COjust a suggestion, or maybe a request, we will be happy if you please to update your mentioned article to also include insertion. I like your webpage design.
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    3. COI modified Rob's code to provide a way of doing this using the newer TArray<T> construction. What do you think, Rob? Any problems I missed?
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