如图：

1.在config配置包中创建一个CorsConfig配置类

2.将下面代码复制到这个类中即可

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
import org.springframework.web.filter.CorsFilter;@Configuration
public class CorsConfig {@Beanpublic CorsFilter corsFilter(){CorsConfiguration corsConfiguration=new CorsConfiguration();corsConfiguration.addAllowedOrigin("*");corsConfiguration.addAllowedHeader("*");corsConfiguration.addAllowedMethod("*");UrlBasedCorsConfigurationSource source=new UrlBasedCorsConfigurationSource();source.registerCorsConfiguration("/**",corsConfiguration);return new CorsFilter(source);}
}