toJson method
Creates a json from the object
Implementation
Map toJson() {
return {
'text': text,
'url': url,
'login_url': loginUrl,
'callback_data': callbackData,
'web_app': webApp,
'switch_inline_query': switchInlineQuery,
'switch_inline_query_current_chat': switchInlineQueryCurrentChat,
'callback_game': callbackGame,
'pay': pay,
}..removeWhere((_, v) => v == null);
}