SpringBoot 解决 ajax 跨域问题

*一、第一种方式:

1、编写一个支持跨域请求的 Configuration

/**

* @author ChenXc

* @version V1.0

* @Date 2018/3/22 17:25

* @Description TODO(跨域支持)

*/

@Configuration

public class CorsConfig extends WebMvcConfigurerAdapter {

@Override

public void addCorsMappings(CorsRegistry registry) {

registry.addMapping("/**")

.allowedOrigins("*")

.allowCredentials(true)

.allowedMethods("GET", "POST", "PUT", "DELETE", "OPTIONS")

.maxAge(3600);

}

}

二、 第二种方式（推荐）

第一种存在一个问题，当服务器抛出 500 的时候依旧存在跨域问题

@SpringBootApplication

@ComponentScan

@EnableDiscoveryClient

public class ManagementApplication {

public static void main(String[] args){

SpringApplication.run(ManagementApplication.class, args);

}

private CorsConfiguration buildConfig() {

CorsConfiguration corsConfiguration = newCorsConfiguration(); 
corsConfiguration.addAllowedOrigin("");
corsConfiguration.addAllowedHeader("*"); 
corsConfiguration.addAllowedMethod("*"); 
corsConfiguration.addExposedHeader(HttpHeaderConStant.X_TOTAL_COUNT); 
return corsConfiguration;

}
/** * 跨域过滤器 * * @return */ 

@Bean

public CorsFilter corsFilter() {

UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource(); 
source.registerCorsConfiguration("/**", buildConfig());
return new CorsFilter(source);

}
}

三、第三种方式，编写 Filter 过滤器

@Component 
public  class OriginFilter implements Filter { 
@Override
public  void init(FilterConfig filterConfig) throws ServletException { 
} 
@Override
public  void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException { 
HttpServletResponse response = (HttpServletResponse) res; 
response.setHeader("Access-Control-Allow-Origin", "*"); 
response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE,PUT"); 
response.setHeader("Access-Control-Max-Age", "3600"); 
response.setHeader("Access-Control-Allow-Headers", "x-requested-with"); 
chain.doFilter(req, res); } 
@Override 
public  void destroy() { 
// TODO Auto-generated method stub 
} 
}