Wordpress get user id by login name

Question

How do i get the user id from user login name in wordpress?

Accepted Answer

By using `get_userdatabylogin`:

```
$user = get_userdatabylogin('loginname');
if($user){
   echo $user->ID;
}
```

Example:

```
$user = get_userdatabylogin('admin');
if($user) echo $user->ID; // Outputs 1
```

UPDATE: the function `get_userdatabylogin` has been deprecated, and replaced with `get_user_by()`. Refer to Dalen's solution to this question.

Solution