Delphi在C/S架构项目中考虑到SQLServer客户端断电的用户登录问题

// 注册已经登录的账户
function TfrmLogin.RegUserLogined(AdoConn: TADOConnection;
AUserID: string): Boolean;
var
Qry: TADOQuery;
SQLStr: string;
begin
//
try
QryCreate(Qry,AdoConn);
try
SQLStr := Format('CREATE TABLE ##XXX%s(%s INT); ', [AUserID, AUserID]);
Qry.SQL.Text := SQLStr;
Qry.ExecSQL;
finally
Qry.Free;
end;
except
Result := False;
Exit;
end;
Result := True;
end;
// 判断账户是否已经登录
function TfrmLogin.ThisUserHadLogined(AdoConn: TADOConnection;
AUserID: string): Boolean;
var
Qry: TADOQuery;
SQLStr: string;
begin
//
try
QryCreate(Qry,AdoConn);
try
SQLStr := Format('SELECT OBJECT_ID(N''tempdb..##XXX%s'', N''U'') AS TabID', [AUserID]);
Qry.SQL.Text := SQLStr;
Qry.Open;
result := not Qry.FieldByName('TabID').IsNull;
finally
Qry.Free;
end;
except
Result := False;
Exit;
end;
end;

procedure TfrmLogin.QryCreate(var aQuery: TADOQuery; Connecion: TAdoConnection);
begin
aQuery := TADOQuery.create(nil);
aQuery.Connection := Connecion;
end;