uses  Data.Cloud.CloudAPI;
...
..
function GetHash_ASPNetMemberShip(const Password, Salt:string):string;
var
  bPassword ,bSalt ,bSaltPassword: TBytes;
begin
   bPassword:= TEncoding.Unicode.GetBytes(Password)  ;
   bSalt:= DecodeBytes64(Salt);
   SetLength(bSaltPassword, length(bPassword)+length(bSalt));
   Move(bSalt[0],bSaltPassword[0],length(bSalt));
  Move(bPassword[0],bSaltPassword[length(bSalt)],length(bPassword));
  Result := THash_SHA1.CalcBuffer(bSaltPassword[0],  Length(bSaltPassword), TFormat_MIME64);
end;