How can I mention Telegram users without a username?

问题

I want mention users even those which do not have a username.

If a user has set up a username I return

Hi @username 

as an answer but if a user does not have one I can't do that.

I tried using the unique User ID e.g.

@5642166

but that did not work.

How can I achieve that?

回答1:

According to official documentation it is possible to mention user by its numerical id with markup:

Markdown style

To use this mode, pass Markdown in the parse_mode field when using sendMessage. Use the following syntax in your message:

[inline mention of a user](tg://user?id=123456789)

and you can also use HTML style :

HTML style

To use this mode, pass HTML in the parse_mode field when using sendMessage. The following tags are currently supported:

<a href="tg://user?id=123456789">inline mention of a user</a>

回答2:

Before I give you an answer I really suggest that you use the first_name attribute of an user. A username is not required if you have a Telegram account, but you have to enter a name.

Here is a code example of how I got the first_name attribute of a user:

$rawContent = file_get_contents("php://input");
$rawContentArray = json_decode($rawContent, true); 

foreach ($rawContentArray as $key => $value) {
    if($key === "message"){
        foreach ($value as $messagekey => $messagevalue) {
            if($messagekey === "chat"){
                foreach ($messagevalue as $chatkey => $chatvalue) {
                    if($chatkey === "first_name"){
                        $first_name = $chatvalue;
                    }
                }
            }
        }
    }
}

If you want to get the username you can do the same, just replace first_name with username and add a simple check after you give $user_name a value:

if($user_name !== ''){
$user_name = "@undefined"}

The problem here is that you have to give a user a placeholder or generic username which is kind of stupid when you think about it. You are giving someone who is using your bot a name. Why do that? But if that's what you want, replace my "@undefined" with your placeholder.

来源：https://stackoverflow.com/questions/40905948/how-can-i-mention-telegram-users-without-a-username