运行出错了,请指教．

[daixiulin]

var
Codes:array[0..2] of Byte;
kuadu:array of Byte;
bMax,bMin:Byte;
str:string;
i,j,s: integer;

begin
SetLength(kuadu,(FCurveList.Count-1));　　//////FCurveList：TStringList;无错
kuadu[j]:=0;
for j:=FCurveList.Count-1 downto 0 do
begin
str:=Copy(FCurveList[j],7,3); //////FCurveList：TStringList;无错
Codes[0]:=Ord(str[1]);
Codes[1]:=Ord(str[2]);
Codes[2]:=Ord(str[3]);
bMax:=Codes[0];
bMin:=Codes[0];
for s:=1 to 2 do
begin
bMax:=Max(bMax, Codes[s]);
bMin:=Min(bMin,Codes[s]);
end;
kuadu[j]:=bMax-bMin;
showmessage(inttostr(kuadu[j]));
end;


说明：求kuadu[j]时，显示invalid pointer operation错误

[gzmhero]

SetLength(kuadu,(FCurveList.Count-1));　　//////FCurveList：TStringList;无错
kuadu[j]:=0; --------------------->这个去掉

[jsweifen]

kuadu[j]:=bMax-bMin; //j的值为-1
showmessage(inttostr(kuadu[j]));

[daixiulin]

SetLength(kuadu,(FCurveList.Count-1));　　//////FCurveList：TStringList;无错

实际有错,呵呵,我原来以为无错,应为SetLength(kuadu,FCurveList.Count);