程序代码：

function CharPos(src:char; str:pchar):Integer;
var
    n:Integer;
Label
    Find,NotFind;
begin
    n:=Length(str);
    asm
        cld;
        lea edi, str;
        mov al,src;
        mov ecx,n;
        repnz scasb;
        jz Find;
        mov result,-1;
        jmp NotFind;
Find:
        mov result,ecx;
NotFind:
    end;
end;

i:=CharPos('e', 'hello word');
    ShowMessage(IntToStr(i));