Writing faster to a memo box 2

[jos100]

Hi !

Any method to load charachters faster in to
a memo box ?

for i:= 1 to 10000 do

memo1.text := memo1.text + x; // x is an array of char.

is slow at the end.

memo1.text := x // not legal.

 

[grg999]

Make up a real string first:

var
S: String; { huge string I hope }

begin
S := '';
for i := 1 to LengthOfArrayX do
S := S + X;

Form1.memo.Text := S; // fast !

 

[towerbase]

Adding characters to the end of a string can be slow for long strings. This time penalty be avoided by using SetLength to set the maximum length of the string before the for loop. So grg999's code can be improved as follows:

var
  s: string;
  ...
begin
  s := '';
  SetLength( s, LengthOfArrayX );
  for i := 1 to LengthOfArrayX do
    s := s + X[i];
end;

Andrew
Hampshire, UK

 

[Griffyn]

If you're not using Delphi 2006, then I would suggest using the FastMM4 memory manager for applications like this

http://sourceforge.net/projects/fastmm

Unzip to ..\Delphi\Lib\FastMM4 preserving the folder structure, add that folder to Delphi's search path, and then modify the .DPR project file of any project you want to use it in and add [tt]FastMM4[/tt] as the first unit in the uses clause. ie.

[b]program[/b] ImportantProg;

[b]uses[/b]
  FastMM4, Forms;
  [navy]// snip[/navy]

This memory manager is much quicker than the Borland's built in one, so much so that Borland included it in Delphi 2006 as the memory manager.