react 全局面包屑

renderBreadcrumb() {
        const {routes} = this.props;
        const items = routes.map((route, idx) => {
            let content = null;
            if (idx == 0) {
                content = <IndexLink to="/">{route.name}</IndexLink>
            } else {
                content = route.name;
            }
            return <Breadcrumb.Item key={idx}>{content}</Breadcrumb.Item>;
        });
        return <Breadcrumb>{items}</Breadcrumb>;
    }

 {this.renderBreadcrumb()}