一开始的解决思路如下：
若依微服务如何解决跨域

发现都行不通，最后通过实现WebFilter接口且重写filter方法解决了此问题，代码如下：

@Component
public class CorsFilter implements WebFilter {
    private static final String MAX_AGE = "3600L";

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, WebFilterChain chain) {
        ServerHttpRequest request = exchange.getRequest();
        if (!CorsUtils.isCorsRequest(request)){
            return  chain.filter(exchange);
        }

        ServerHttpResponse response = exchange.getResponse();
        HttpHeaders headers = response.getHeaders();
        headers.add("Access-Control-Allow-Origin","*");
        headers.add("Access-Control-Allow-Methods", "*");
        headers.add("Access-Control-Allow-Headers", "*");
        headers.add("Access-Control-Max-Age", MAX_AGE);
        if (request.getMethod() == org.springframework.http.HttpMethod.OPTIONS) {
            response.setStatusCode(org.springframework.http.HttpStatus.OK);
            return Mono.empty();
        }
        return chain.filter(exchange);
    }
}

和定义Webfilter的bean很像，但是不知道为什么定义bean始终无法解决跨域问题，也欢迎大家一起来讨论一下。