怎样取一个字符在字符串中的最后出现的位置

Question

如WebServices中怎样取s为11

Answer 1

function posend(sub:char;s:string):integer;
var
 i:integer;
 temp:string;
begin
 temp:=ReverseString(s);//Unit StrUtils
 i:=pos(sub,temp);
 result:=length(s)+1-i;
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
  showmessage(inttostr(posend('e','webservices')));
end;

Answer 2

while pos(substr,str,)>0 

Answer 3

var i:integer;
begin
  i:=Length('WebServices');
  edit1.Text :=inttostr(i);   //result:edit1.text=11
end;

Answer 4

procedure TForm1.Button1Click(Sender: TObject);
var
s:string;
i:integer;
begin
s:='WebServices';
i:=0;
while pos('s',s)> 0 do
   begin
   i:=i+pos('s',s);
   delete(s,1,pos('s',s));
   pos('s',s);
   end;
showmessage(inttostr(i));
测试通过了

Answer 5

function PosEnd(var substr,s:string):integer;
 var
 i:integer;
begin
    i:=0;
 while pos(substr,s)>0 do
      begin
      i:=i+pos(substr,s);
      Delete(s,1,pos(substr,s));
      pos(substr,s);
      end;
 result:=i;end;