# switchRole method Null safety

Future<void> switchRole(

1. int role

)

Switch roles (applicable only to the live streaming scenarios `TRTC_APP_SCENE_LIVE` and `TRTC_APP_SCENE_VOICE_CHATROOM`)

In the live streaming scenario, a user may need to switch between "audience" and "anchor" roles. You can use the `role` field in `TRTCParams` before room entry to determine the role or use the `switchRole` API to switch roles after room entry.

param:

role Target role, which is anchor by default:

TRTCCloudDef.TRTCRoleAnchor: anchor, who can upstream video and audio. Up to 50 anchors are allowed to upstream videos at the same time in one room.

TRTCCloudDef.TRTCRoleAudience: audience, who can only watch the video but cannot upstream video or audio. There is no upper limit for the number of audience users in one room.

## Implementation

    Future<void> switchRole(int role // Target role, which is anchor by default:
        ) {
      return _channel.invokeMethod('switchRole', {
        "role": role,
      });
    }