用了Case,Copy实现了这个功能有兴趣下载试试
这个程序就类似与文本的查找搜索功能!

代码:

Var Str :String;
ii :Integer;

procedure TForm1.Button1Click(Sender: TObject);
Var
Change,i :Integer;
begin
Case RG.Checked of
False:
begin
if Pos(FindEd.Text,Str) = 0 then
MessageBox(Handle,'找不到你要的字符','出错',MB_OK)
else
begin
Change :=Pos(FindED.text,Str);
ii :=Change+ii;
Str :=Copy(Str,Change+1,Length(Str)-Change+1);
OutLB.Caption :=InttoStr(ii);
end;
end;
True:
begin
Change :=Pos(FindED.text,Str);
ii :=Change+ii;
Str :=Copy(Str,Change+1,Length(Str)-Change+1);
OutLB.Caption :=InttoStr(ii);
if Change = 0 then
begin
ii :=0;
Str :=WideString(InputEd.Text);
end;
end;
end;

end;

procedure TForm1.InputEDChange(Sender: TObject);
begin
ii :=0;
Str :=WideString(InputEd.Text);
end;