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unit
Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;
type
TForm1 = class
(TForm)
Button1: TButton;
procedure
Button1Click(Sender: TObject);
end
;
var
Form1: TForm1;
implementation
{$R *.dfm}
//ÅжÏÒ»¸ö×Ö·û´®ÖÐÊý×ֵĸöÊý
function
GetNum1(str: string
): Integer;
var
i: Integer;
begin
Result := 0
;
for
i := 1
to
Length(str) do
if
str[i] in
['0'
..'9'
] then
Inc(Result);
end
;
//ͬÑùµÄº¯ÊýÖ»ÊǸø²ÎÊý¼ÓÉÏ const
function
GetNum2(const
str: string
): Integer;
var
i: Integer;
begin
Result := 0
;
for
i := 1
to
Length(str) do
if
str[i] in
['0'
..'9'
] then
Inc(Result);
end
;
{¶Ô±È²âÊÔ}
procedure
TForm1.Button1Click(Sender: TObject);
var
s: string
;
n: Cardinal;
i: Integer;
begin
s := 'ABC123'
;
n := GetTickCount;
for
i := 0
to
1000000
do
GetNum1(s);
n := GetTickCount - n;
Text := IntToStr(n) + ' - '
;
n := GetTickCount;
for
i := 0
to
1000000
do
GetNum2(s);
n := GetTickCount - n;
Text := Text + IntToStr(n);
end
;
end
.