Overview

This document provides an overview of APIs and SDK code samples related to listing objects.

API	Operation	Description
GET Bucket (List Objects)	Querying objects	Queries some or all the objects in a bucket.
GET Bucket Object Versions	Querying objects and their version history	Queries some or all the objects in a bucket and their version history.

SDK API References

For the parameters and method description of all the APIs in the SDK, see API Documentation.

Querying an Object List

Description

This API is used to query some or all the objects in a bucket.

Sample 1. Getting the first page of data

try
{
// Bucket name in the format of bucketname-APPID. You can get APPID by referring to https://console.cloud.tencent.com/developer.
string bucket = "examplebucket-1250000000";
GetBucketRequest request = new GetBucketRequest(bucket);
// Execute the request
GetBucketResult result = cosXml.GetBucket(request);
// Bucket information
ListBucket info = result.listBucket;
if (info.isTruncated) {
  // The data is truncated, and the next marker of the data is recorded.
  this.nextMarker = info.nextMarker;
}
}
catch (COSXML.CosException.CosClientException clientEx)
{
// Request failed
Console.WriteLine("CosClientException: " + clientEx);
}
catch (COSXML.CosException.CosServerException serverEx)
{
// Request failed
Console.WriteLine("CosServerException: " + serverEx.GetInfo());
}

Note：

For the complete sample, go to GitHub.

Sample 2. Requesting the next page of data

try
{
// Bucket name in the format of bucketname-APPID. You can get APPID by referring to https://console.cloud.tencent.com/developer.
string bucket = "examplebucket-1250000000";
GetBucketRequest request = new GetBucketRequest(bucket);
// Use the “nextMarker” from the previous request
request.SetMarker(this.nextMarker);
// Execute the request
GetBucketResult result = cosXml.GetBucket(request);
// Bucket information
ListBucket info = result.listBucket;
}
catch (COSXML.CosException.CosClientException clientEx)
{
// Request failed
Console.WriteLine("CosClientException: " + clientEx);
}
catch (COSXML.CosException.CosServerException serverEx)
{
// Request failed
Console.WriteLine("CosServerException: " + serverEx.GetInfo());
}

Note：

For the complete sample, go to GitHub.

Sample 3. Getting an object list and subdirectories

try
{
// Bucket name in the format of bucketname-APPID. You can get APPID by referring to https://console.cloud.tencent.com/developer.
string bucket = "examplebucket-1250000000";
GetBucketRequest request = new GetBucketRequest(bucket);
// Get the objects and subdirectories under “a/”
request.SetPrefix("a/");
request.SetDelimiter("/");
// Execute the request
GetBucketResult result = cosXml.GetBucket(request);
// Bucket information
ListBucket info = result.listBucket;
// List objects
List<ListBucket.Contents> objects = info.contentsList;
// List common prefixes
List<ListBucket.CommonPrefixes> subDirs = info.commonPrefixesList;
}
catch (COSXML.CosException.CosClientException clientEx)
{
// Request failed
Console.WriteLine("CosClientException: " + clientEx);
}
catch (COSXML.CosException.CosServerException serverEx)
{
// Request failed
Console.WriteLine("CosServerException: " + serverEx.GetInfo());
}

Note：

For the complete sample, go to GitHub.

Querying an Object Version List

Description

This API is used to query some or all objects in a versioning-enabled bucket.

Sample 1. Getting the object version list’s first page of data

try
{
// Bucket name in the format of bucketname-APPID. You can get APPID by referring to https://console.cloud.tencent.com/developer.
string bucket = "examplebucket-1250000000";
ListBucketVersionsRequest request = new ListBucketVersionsRequest(bucket);
// Execute the request
ListBucketVersionsResult result = cosXml.ListBucketVersions(request);
// Bucket information
ListBucketVersions info = result.listBucketVersions;
 List<ListBucketVersions.Version> objects = info.objectVersionList;
List<ListBucketVersions.CommonPrefixes> prefixes = info.commonPrefixesList;
 if (info.isTruncated) {
  // The data is truncated, and the next marker of the data is recorded.
  this.keyMarker = info.nextKeyMarker;
  this.versionIdMarker = info.nextVersionIdMarker;
}
}
catch (COSXML.CosException.CosClientException clientEx)
{
// Request failed
Console.WriteLine("CosClientException: " + clientEx);
}
catch (COSXML.CosException.CosServerException serverEx)
{
// Request failed
Console.WriteLine("CosServerException: " + serverEx.GetInfo());
}

Note：

For the complete sample, go to GitHub.

Sample 2. Getting the object version list’s next page of data

try
{
// Bucket name in the format of bucketname-APPID. You can get APPID by referring to https://console.cloud.tencent.com/developer.
string bucket = "examplebucket-1250000000";
ListBucketVersionsRequest request = new ListBucketVersionsRequest(bucket);
 // Use the “nextMarker” from the previous request
request.SetKeyMarker(this.keyMarker);
request.SetVersionIdMarker(this.versionIdMarker);
 // Execute the request
ListBucketVersionsResult result = cosXml.ListBucketVersions(request);
ListBucketVersions info = result.listBucketVersions;
 if (info.isTruncated) {
  // The data is truncated, and the next marker of the data is recorded.
  this.keyMarker = info.nextKeyMarker;
  this.versionIdMarker = info.nextVersionIdMarker;
}
}
catch (COSXML.CosException.CosClientException clientEx)
{
// Request failed
Console.WriteLine("CosClientException: " + clientEx);
}
catch (COSXML.CosException.CosServerException serverEx)
{
// Request failed
Console.WriteLine("CosServerException: " + serverEx.GetInfo());
}

Note：

For the complete sample, go to GitHub.