我如何设置初始化 var c#？

Question

I'm new in c# and have this var:

var updates = await Bot.GetUpdatesAsync(offset);

but now want updates define other scope and use it with this shape:

updates = await Bot.GetUpdatesAsync(offset);

try define with this code:

var updates =(string) null;

but in this line c# compiler get this error:

    updates = await Bot.GetUpdatesAsync(offset);
(awaitable)Task<Update[]> TelegramBotClient.GetUpdatesAsync([int offset=0],[int limit=100],[int timeout=0],[CancellationToken cancellationToken=default(CancellationToken)
use this method recieve incoming updates using long polling.
Usage:
Update[] x=await GetUpdateAsync(...);
Can not implicitly convert type 'Telegram.Bot.Types.Update[]' to 'string'

How can i solve this code ?thanks:

var updates =(string) null;

Answer 1

Obviously, return type of your method is not a string , but Telegram.Bot.Types.Update[] .

So you can change the code to

Telegram.Bot.Types.Update[] updates;
// the rest of code
updates = await Bot.GetUpdatesAsync(offset);

Answer 2

Replace var updates =(string) null; with var updates =(Telegram.Bot.Types.Update[]) null;