大家好，我最近在做Spring Boot后端搭配Angular前端的项目时，遇到了CORS跨域拦截的问题，折腾好久都没解决，想请各位帮忙看看！

我遇到的错误提示如下：

Access to XMLHttpRequest at 'http://127.0.0.1:8082/api/cvs/recrutement' from origin 'http://localhost:4200' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.

情况是这样的：用Postman调用Spring Boot的API完全正常，没有任何错误，但用Angular前端调用时，就会弹出上面这个blocked by CORS policy的错误。

下面是我的相关代码：

后端Spring Boot的Controller代码 #

@RestController
@CrossOrigin(origins = "http://localhost:4200")
public class CSVController {

  @Autowired  CSVService fileService;
  @Autowired CandidatRepository  dao;
   
  @GetMapping("/api/cvs/recrutement")
  @PreAuthorize("hasRole('RH') or hasRole('FINANCE') or hasRole('ADMIN')")
  public ResponseEntity<List<Candidat>> getAllCandidats() {
    try {
      List<Candidat> Candidats = fileService.getAllTutorials();

      if (Candidats.isEmpty()) {
        return new ResponseEntity<>(HttpStatus.NO_CONTENT);
      }

      return new ResponseEntity<>(Candidats, HttpStatus.OK);
    } catch (Exception e) {
      return new ResponseEntity<>(null, HttpStatus.INTERNAL_SERVER_ERROR);
    }
  }
}

后端的CORS配置类 #

public class CorsConfig implements WebMvcConfigurer{

  @Bean
  public WebMvcConfigurer corsConfigurer() {
    System.out.println("CORS Config success");

    return new WebMvcConfigurer() {

      @Override
      public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**").allowedOrigins("http://localhost:4200"); // "/create-cars"
      }
    };

  }
}

Angular前端的组件代码（component.ts） #

getAllCandidat() {
  this._dao.findAllCandidat().subscribe(resp=>{
    this.ExcelData = resp
  })
}

Angular前端的服务代码 #

findAllCandidat() {
  return this.http.get<any[]>(`${BASIC_URL}api/cvs/recrutement`)
}

有没有大佬能帮我看看问题出在哪呀？谢谢大家！

备注：内容来源于stack exchange，提问作者King Kapeta