方法1:推薦方便。
System.Hash 單元
Memo1.Lines.Add(THash.GetRandomString(50));

方法二(自己寫的):
function TStrApi.SuiJiString(const AWeiShu: Integer): string;
const
SourceStr: string = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
var
MyRep: string;
I: Integer;
begin
Randomize;
for I := 1 to AWeiShu do
begin
//這里只所以必須加1,是因為SourceStr是從1開始的,而Random是從0開始的,SourceStr[0]就會報錯,SourceStr[63]也會報錯
MyRep := MyRep + SourceStr[Random(61)+1];
end;
Exit(MyRep);
end;
PK結果,效率差不多。:
procedure TForm6.Button1Click(Sender: TObject);
var
I: Integer;
startTime: Cardinal;
strResult: string;
begin
startTime := GetTickCount;
for I := 1 to 10000 do
begin
strResult := THash.GetRandomString(50);
end;
Label1.Caption := '耗時: ' + (GetTickCount - startTime).ToString;
end;
procedure TForm6.Button2Click(Sender: TObject);
const
SourceStr: string = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
var
strResult: string;
I,K: Integer;
startTime: Cardinal;
begin
startTime := GetTickCount;
for I := 1 to 10000 do
begin
Randomize;
strResult := '';
for K := 1 to 50 do
begin
//這里只所以必須加1,是因為SourceStr是從1開始的,而Random是從0開始的,SourceStr[0]就會報錯,SourceStr[63]也會報錯
strResult := strResult + SourceStr[Random(61)+1];
end;
end;
Label1.Caption := '耗時: ' + (GetTickCount - startTime).ToString;
end;

http://www.cnblogs.com/del88/p/6911709.html

