# 查看跨域规则
![](https://support.huaweicloud.com/sdk-dotnet-devg-obs/public_sys-resources/notice_3.0-zh-cn.png)
开发过程中，您有任何问题可以在github上[提交issue](https://github.com/huaweicloud/huaweicloud-sdk-dotnet-obs/issues)，或者在[华为云对象存储服务论坛](https://bbs.huaweicloud.com/forum/forum-620-1.html)中发帖求助。[接口参考文档](https://obssdk.obs.cn-north-1.myhuaweicloud.com/apidoc/cn/dotnet/html/G_OBS.htm)详细介绍了每个接口的参数和使用方法。
您可以通过ObsClient.GetBucketCors查看桶的跨域规则。
本示例用于查看桶名为"bucketname"的跨域规则。
代码示例如下所示:
```
// 初始化配置参数
ObsConfig config = new ObsConfig();
config.Endpoint = "https://your-endpoint";
// 认证用的ak和sk硬编码到代码中或者明文存储都有很大的安全风险，建议在配置文件或者环境变量中密文存放，使用时解密，确保安全；本示例以ak和sk保存在环境变量中为例，运行本示例前请先在本地环境中设置环境变量AccessKeyID和SecretAccessKey。
// 您可以登录访问管理控制台获取访问密钥AK/SK，获取方式请参见https://support.huaweicloud.com/usermanual-ca/ca_01_0003.html
string accessKey= Environment.GetEnvironmentVariable("AccessKeyID", EnvironmentVariableTarget.Machine);
string secretKey= Environment.GetEnvironmentVariable("SecretAccessKey", EnvironmentVariableTarget.Machine);
// 创建ObsClient实例
ObsClient client = new ObsClient(accessKey, secretKey, config);
// 查看跨域规则
try
{
    GetBucketCorsRequest request = new GetBucketCorsRequest();
    request.BucketName = "bucketname";
    GetBucketCorsResponse response = client.GetBucketCors(request);
    foreach (CorsRule rule in response.Configuration.Rules)
    {
        Console.WriteLine("rule id is: {0}\n", rule.Id);
        foreach (string allowOrigin in rule.AllowedOrigins)
        {
            Console.WriteLine("allowOrigin is: {0}\n", allowOrigin);
        }
        foreach (string allowHeader in rule.AllowedHeaders)
        {
            Console.WriteLine("allowHeader is: {0}\n", allowHeader);
        }
        foreach (HttpVerb allowMethod in rule.AllowedMethods)
        {
            Console.WriteLine("allowMethod is: {0}\n", allowMethod);
        }
        foreach (string exposeHeader in rule.ExposeHeaders)
        {
            Console.WriteLine("exposeHeader is: {0}\n", exposeHeader);
        }
        Console.WriteLine("rule maxAgeSeconds is: {0}\n", rule.MaxAgeSeconds);
    }
}
catch (ObsException ex)
{
    Console.WriteLine("ErrorCode: {0}", ex.ErrorCode);
    Console.WriteLine("ErrorMessage: {0}", ex.ErrorMessage);
}
```
![](https://support.huaweicloud.com/sdk-dotnet-devg-obs/public_sys-resources/note_3.0-zh-cn.png)
查看跨域规则过程中返回的错误码含义、问题原因及处理措施可参考[SDK错误码](https://support.huaweicloud.com/sdk-dotnet-devg-obs/obs_25_1606.html)。