Fastest (most efficient) way to initialize a large array of records

Hello experts, I've got a record and variable defined like this:

  TMyRecord = record
    FieldStart: Integer;
    FieldEnd: Integer;
    IsEmptyField : Boolean;

  MyArray : array of TMyRecord;  / / dynamic array

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I need to re-initialize this array upon every line I read from my data file on disk (could be large), and currently I use:

SetLength(MyArray, 0);

Ths works fine, but I think it may be a little inefficient and slowing down overall execution. I was wondering if there's a faster way to initialize this. I also realize that having it as a dynamic array and resizing it during processing slows things down too. I'm thinking of making the array a constant big size that ought to handle every case, and declare it like so:

MyArray : array[0..10000] of TMyRecord;

So then, what would be the most efficient way to initialize this array of records? Googling around I've seen a few methods: using "Default", "FillChar", "Initialize"... or even a FOR loop to individually loop around and set each record element to 0 (or FALSE for the boolean). Would anyone have any advice please?


P.S: I use Delphi 7
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Sinisa VukSoftware architectCommented:
Think best is using static array (predefined number) of records like you said:
MyArray : array[0..10000] of TMyRecord;

Clearing is fastest using:

ZeroMemory(@MyArray, SizeOf(MyArray));

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I go from dynamic array to static one - because of same reason...

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shawn857Author Commented:
Very good, thanks Sinisa.

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