trimstr.pas

《delphi数据库系统开发实例导航》源代码

unit TrimStr;

interface
Const
  Space=#$20;
  function LTrim(Str:String):String;
  function RTrim(Str:String):String;
  function Trim(Str:String):String;
implementation

function LTrim(Str:String):String;
var
  len:Byte absolute Str;
  i:Integer;
begin
  i:=1;
  while(i<=len) and (Str[i]=Space) do Inc(i);
  LTrim:=Copy(Str, i, len-i+1);
end;

function RTrim(Str:String):String;
var
  len:Byte absolute Str;
begin
  while(Str[len]=Space) do Dec(len);
  RTrim:=Str;
end;

function Trim(Str:String):String;
begin
  Trim:=LTrim(RTrim(Str));
end;

end.