OSS支持设置生命周期（Lifecycle）规则，自动删除过期的文件和碎片，或将到期的文件转储为低频或归档存储类型，从而节省存储费用。本文介绍如何管理生命周期规则。

using Aliyun.OSS;
using Aliyun.OSS.Common;
var endpoint = "<yourEndpoint>";
var accessKeyId = "<yourAccessKeyId>";
var accessKeySecret = "<yourAccessKeySecret>";
var bucketName = "<yourBucketName>";
// 创建OSSClient实例。
var client = new OssClient(endpoint, accessKeyId, accessKeySecret);
try
{
    var setBucketLifecycleRequest = new SetBucketLifecycleRequest(bucketName);
    // 创建第1条生命周期规则。
    LifecycleRule lcr1 = new LifecycleRule()
    {
        ID = "delete obsoleted files",
        Prefix = "obsoleted/",
        Status = RuleStatus.Enabled,
        ExpriationDays = 3,
        Tags = new Tag[1]
    };
    // 设置标签。
    var tag1 = new Tag
    {
        Key = "project",
        Value = "projectone"
    };

    lcr1.Tags[0] = tag1;

    // 创建第2条生命周期规则。
    LifecycleRule lcr2 = new LifecycleRule()
    {
        ID = "delete temporary files",
        Prefix = "temporary/",
        Status = RuleStatus.Enabled,
        ExpriationDays = 20,
        Tags = new Tag[1]         
    };
    // 设置标签。
    var tag2 = new Tag
    {
        Key = "user",
        Value = "jsmith"
    };
    lcr2.Tags[0] = tag2;

    // 设置碎片在距最后修改时间30天后过期。
    lcr2.AbortMultipartUpload = new LifecycleRule.LifeCycleExpiration()
    {
        Days = 30
    };

    LifecycleRule lcr3 = new LifecycleRule();
    lcr3.ID = "only NoncurrentVersionTransition";
    lcr3.Prefix = "test1";
    lcr3.Status = RuleStatus.Enabled;
    lcr3.NoncurrentVersionTransitions = new LifecycleRule.LifeCycleNoncurrentVersionTransition[2]
    {
        // 设置非当前版本的Object距最后修改时间90天之后转为低频访问类型。
        new LifecycleRule.LifeCycleNoncurrentVersionTransition(){
            StorageClass = StorageClass.IA,
            NoncurrentDays = 90
        },
        // 设置非当前版本的Object距最后修改时间180天之后转为归档类型。
        new LifecycleRule.LifeCycleNoncurrentVersionTransition(){
            StorageClass = StorageClass.Archive,
            NoncurrentDays = 180
        }
    };
    setBucketLifecycleRequest.AddLifecycleRule(lcr1);
    setBucketLifecycleRequest.AddLifecycleRule(lcr2);
    setBucketLifecycleRequest.AddLifecycleRule(lcr3);

    // 设置生命周期规则。
    client.SetBucketLifecycle(setBucketLifecycleRequest);
    Console.WriteLine("Set bucket:{0} Lifecycle succeeded ", bucketName);
}
catch (OssException ex)
{
    Console.WriteLine("Failed with error code: {0}; Error info: {1}. \nRequestID:{2}\tHostID:{3}",
        ex.ErrorCode, ex.Message, ex.RequestId, ex.HostId);
}
catch (Exception ex)
{
    Console.WriteLine("Failed with error info: {0}", ex.Message);
}

using Aliyun.OSS;
using Aliyun.OSS.Common;
var endpoint = "<yourEndpoint>";
var accessKeyId = "<yourAccessKeyId>";
var accessKeySecret = "<yourAccessKeySecret>";
var bucketName = "<yourBucketName>";
// 创建OSSClient实例。
var client = new OssClient(endpoint, accessKeyId, accessKeySecret);
try
{
    // 查看生命周期规则。
    var rules = client.GetBucketLifecycle(bucketName);
    Console.WriteLine("Get bucket:{0} Lifecycle succeeded ", bucketName);
    foreach (var rule in rules)
    {
        Console.WriteLine("ID: {0}", rule.ID);
        Console.WriteLine("Prefix: {0}", rule.Prefix);
        Console.WriteLine("Status: {0}", rule.Status);
        // 查看标签信息。
        foreach (var tag in rule.Tags)
        {
            Console.WriteLine("key:{0}, value:{1}", tag.Key, tag.Value);
        }
        // 查看非当前版本Object过期规则。
        foreach (var version in rule.NoncurrentVersionTransitions)
        {
            Console.WriteLine("expiration day:{0}, storage class:{1}", version.NoncurrentDays, version.StorageClass);
        }
        if (rule.ExpriationDays.HasValue)
            Console.WriteLine("ExpirationDays: {0}", rule.ExpriationDays);
    }
}
catch (OssException ex)
{
    Console.WriteLine("Failed with error code: {0}; Error info: {1}. \nRequestID:{2}\tHostID:{3}",
        ex.ErrorCode, ex.Message, ex.RequestId, ex.HostId);
}
catch (Exception ex)
{
    Console.WriteLine("Failed with error info: {0}", ex.Message);
}

using Aliyun.OSS;
using Aliyun.OSS.Common;
var endpoint = "<yourEndpoint>";
var accessKeyId = "<yourAccessKeyId>";
var accessKeySecret = "<yourAccessKeySecret>";
var bucketName = "<yourBucketName>";
// 创建OSSClient实例。
var client = new OssClient(endpoint, accessKeyId, accessKeySecret);
try
{
    // 清空生命周期规则。
    client.DeleteBucketLifecycle(bucketName);
    Console.WriteLine("Delete bucket:{0} Lifecycle succeeded ", bucketName);
}
catch (OssException ex)
{
    Console.WriteLine("Failed with error code: {0}; Error info: {1}. \nRequestID:{2}\tHostID:{3}",
        ex.ErrorCode, ex.Message, ex.RequestId, ex.HostId);
}
catch (Exception ex)
{
    Console.WriteLine("Failed with error info: {0}", ex.Message);
}