解题：(小问题)

如果你是在文本框输入一串字符.
procedure TForm1.Button1Click(Sender: TObject);
var
str: string;
msg:string;
i,a,b,c,d: integer;
begin
a:=0;b:=0;c:=0;d:=0;
str:=edit1.Text;
for i:=1 to length(edit1.Text) do
begin
if str[i]=' ' then
inc(a)
else if str[i] in ['0'..'9'] then
inc(b)
else if ('A'<str[i]) and (str[i]<'z')then
inc(c)
else
inc(d);

end;
msg:='空格的个数是:'+inttostr(a)+'数字的个数是：'+inttostr(b)+'字母的个数是：'+inttostr(c)+'其他符号的个数：'+inttostr(d);
showmessage(msg);
end;