解决跨域问题

在后端解决跨域问题：
新建配置类 config/ CrosConfig.java

/*** 解决跨域问题*/
@Configuration
public class CrosConfig implements WebMvcConfigurer {@Overridepublic void addCorsMappings(CorsRegistry registry) {registry.addMapping("/**").allowedOrigins("*").allowedMethods("GET", "HEAD", "POST", "PUT", "DELETE", "OPTIONS").allowCredentials(true).maxAge(3600).allowedHeaders("*");}
}