主要是通过 Config::set 来重新定义

\Config::set('jwt.user' , "App\Models\Admin"); \Config::set('auth.providers.users.model', \App\Models\Admin::class);

完整代码如下：

public function login(Request $request){
    if($token = JWTAuth::getToken()){
        try{
            JWTAuth::invalidate($token);
        } catch(\Exception $e){}
    }
    $credentials = $request->only('email', 'password');
    \Config::set('jwt.user' , "App\Models\Admin");
    \Config::set('auth.providers.users.model', \App\Models\Admin::class);
    if (! $token = JWTAuth::attempt($credentials)) {
        return response()->json(['success' => false, 'msg' => '用户名或密码错误'], 401);
     }
    return response()->json(['success' => true,'token' => $token,'email' => $request- 
                             >input('email'),'username' => auth()->user()->name]);
}