得到一个临时的文件名称

function GetExePath: string;
begin
  Result := ExtractFilePath(ParamStr(0));

end;

function GetTempFileName: string;
var
  vPath: string;
begin
  SetLength(Result, 255);
  GetTempFileName(PChar(GetExePath), PChar('~'), 0, PChar(result));
   
  vPath := GetExePath + 'temp\';
  if not SysUtils.DirectoryExists(vPath) then
    SysUtils.ForceDirectories(vPath);

  result := PChar(Result); //去掉多余的空字符

  Result := vPath + ExtractFileName(Result);
end;