因为我的项目是springBoot+vue的前后端分离项目，我在开发时使用proxy代理实现前后端跨域请求

proxyTable: {
      '/': {
      target: 'http://localhost:8080', // 接口的域名
      // secure: false,  // 如果是https接口，需要配置这个参数
      changeOrigin: true, // 如果接口跨域，需要进行这个参数配置
      pathRewrite: {
        '/': '/'
      }
  }
},

所以在springBoot的websocket配置文件开启sockjs时加上准许跨域setAllowedOrigins("")
The method **setAllowedOrigins("")** is used to CORS-enable the server so cross-origin clients can connect to the server. If your requirements do not need cross-origin client connection, you can remove this invocation.

public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
    @Override
    public void registerStompEndpoints(StompEndpointRegistry stompEndpointRegistry) {
   	stompEndpointRegistry.addEndpoint("/ws/endpointChat").setAllowedOrigins("*").withSockJS();
    }

    @Override
    public void configureMessageBroker(MessageBrokerRegistry registry) {
        registry.enableSimpleBroker("/queue","/topic");
    }
}