本文介绍如何列举指定存储空间(Bucket)的所有文件、指定个数的文件以及指定目录下的文件大小等。
背景信息
OSS 文件按照字母顺序排列。您可以通过OssClient.ListObjects列出存储空间下的文件。ListObjects有以下三类参数格式:
ListObjectOutcome ListObjects(const std::string& bucket) const:列举存储空间下的文件。最多列举1000个文件。
ListObjectOutcome ListObjects(const std::string& bucket, const std::string& prefix) const: 列举存储空间下指定前缀的文件。最多列举 1000 个文件。
ListObjectOutcome ListObjects(const ListObjectsRequest& request) const:提供多种过滤功能,实现灵活的查询功能。
主要参数及说明如下:
参数 | 描述 |
delimiter | 对文件名称进行分组的一个字符。所有名称包含指定的前缀且第一次出现delimiter字符之间的文件作为一组(commonPrefixes)。 |
prefix | 限定返回的文件必须以prefix作为前缀。 |
maxKeys | 限定此次列举文件的最大个数。默认值为100,最大值为1000。 |
marker | 列举指定marker之后的文件。 |
注意事项
本文以华东1(杭州)外网Endpoint为例。如果您希望通过与OSS同地域的其他阿里云产品访问OSS,请使用内网Endpoint。关于OSS支持的Region与Endpoint的对应关系,请参见OSS地域和访问域名。
本文以OSS域名新建OSSClient为例。如果您希望通过自定义域名、STS等方式新建OSSClient,请参见新建OssClient。
要列举文件,您必须有
oss:ListObjects
权限。具体操作,请参见为RAM用户授权自定义的权限策略。
简单列举文件
以下代码用于列举指定存储空间下的文件,默认列举100个文件。
#include <alibabacloud/oss/OssClient.h>
using namespace AlibabaCloud::OSS;
int main(void)
{
/* 初始化OSS账号信息。*/
/* yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1(杭州)为例,Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。*/
std::string Endpoint = "yourEndpoint";
/* yourRegion填写Bucket所在地域对应的Region。以华东1(杭州)为例,Region填写为cn-hangzhou。*/
std::string Region = "yourRegion";
/* 填写Bucket名称,例如examplebucket。*/
std::string BucketName = "examplebucket";
/* 初始化网络等资源。*/
InitializeSdk();
ClientConfiguration conf;
conf.signatureVersion = SignatureVersionType::V4;
/* 从环境变量中获取访问凭证。运行本代码示例之前,请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。*/
auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>();
OssClient client(Endpoint, credentialsProvider, conf);
client.SetRegion(Region);
/* 列举文件。*/
ListObjectsRequest request(BucketName);
auto outcome = client.ListObjects(request);
if (!outcome.isSuccess()) {
/* 异常处理。*/
std::cout << "ListObjects fail" <<
",code:" << outcome.error().Code() <<
",message:" << outcome.error().Message() <<
",requestId:" << outcome.error().RequestId() << std::endl;
return -1;
}
else {
for (const auto& object : outcome.result().ObjectSummarys()) {
std::cout << "object"<<
",name:" << object.Key() <<
",size:" << object.Size() <<
",lastmodify time:" << object.LastModified() << std:: endl;
}
}
/* 释放网络等资源。*/
ShutdownSdk();
return 0;
}
列举指定个数的文件
以下代码用于列举指定个数的文件。
#include <alibabacloud/oss/OssClient.h>
using namespace AlibabaCloud::OSS;
int main(void)
{
/* 初始化OSS账号信息。*/
/* yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1(杭州)为例,Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。*/
std::string Endpoint = "yourEndpoint";
/* yourRegion填写Bucket所在地域对应的Region。以华东1(杭州)为例,Region填写为cn-hangzhou。*/
std::string Region = "yourRegion";
/* 填写Bucket名称,例如examplebucket。*/
std::string BucketName = "examplebucket";
/* 初始化网络等资源。*/
InitializeSdk();
ClientConfiguration conf;
conf.signatureVersion = SignatureVersionType::V4;
/* 从环境变量中获取访问凭证。运行本代码示例之前,请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。*/
auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>();
OssClient client(Endpoint, credentialsProvider, conf);
client.SetRegion(Region);
/* 列举文件。*/
ListObjectsRequest request(BucketName);
/* 设置列举文件的最大个数为200。*/
request.setMaxKeys(200);
auto outcome = client.ListObjects(request);
if (!outcome.isSuccess( )) {
/* 异常处理。*/
std::cout << "ListObjects fail" <<
",code:" << outcome.error().Code() <<
",message:" << outcome.error().Message() <<
",requestId:" << outcome.error().RequestId() << std::endl;
return -1;
}
else {
for (const auto& object : outcome.result().ObjectSummarys()) {
std::cout << "object"<<
",name:" << object.Key() <<
",size:" << object.Size() <<
",lastmodify time:" << object.LastModified() << std ::endl;
}
}
/* 释放网络等资源。*/
ShutdownSdk();
return 0;
}
列举指定目录下的文件和子目录
以下代码用于列举指定目录下的文件和子目录:
#include <alibabacloud/oss/OssClient.h>
using namespace AlibabaCloud::OSS;
int main(void)
{
/* 初始化OSS账号信息。*/
/* yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1(杭州)为例,Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。*/
std::string Endpoint = "yourEndpoint";
/* yourRegion填写Bucket所在地域对应的Region。以华东1(杭州)为例,Region填写为cn-hangzhou。*/
std::string Region = "yourRegion";
/* 填写Bucket名称,例如examplebucket。*/
std::string BucketName = "examplebucket";
/* 填写列举的文件前缀(Prefix)。*/
std::string keyPrefix = "yourkeyPrefix";
/* 初始化网络等资源。*/
InitializeSdk();
ClientConfiguration conf;
conf.signatureVersion = SignatureVersionType::V4;
/* 从环境变量中获取访问凭证。运行本代码示例之前,请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。*/
auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>();
OssClient client(Endpoint, credentialsProvider, conf);
client.SetRegion(Region);
std::string nextMarker = "";
bool isTruncated = false;
do {
/* 列举文件。*/
ListObjectsRequest request(BucketName);
/* 设置正斜线(/)为文件夹的分隔符 */
request.setDelimiter("/");
request.setPrefix(keyPrefix);
request.setMarker(nextMarker);
auto outcome = client.ListObjects(request);
if (!outcome.isSuccess ()) {
/* 异常处理。*/
std::cout << "ListObjects fail" <<
",code:" << outcome.error().Code() <<
",message:" << outcome.error().Message() <<
",requestId:" << outcome.error().RequestId() << std::endl;
break;
}
for (const auto& object : outcome.result().ObjectSummarys()) {
std::cout << "object"<<
",name:" << object.Key() <<
",size:" << object.Size() <<
",lastmodify time:" << object.LastModified() << std::endl;
}
for (const auto& commonPrefix : outcome.result().CommonPrefixes()) {
std::cout << "commonPrefix" << ",name:" << commonPrefix << std::endl;
}
nextMarker = outcome.result().NextMarker();
isTruncated = outcome.result().IsTruncated();
} while (isTruncated);
/* 释放网络等资源。*/
ShutdownSdk();
return 0;
}
列举指定目录下的文件大小
以下代码用于获取指定目录下的文件大小:
#include <iostream>
#include <alibabacloud/oss/OssClient.h>
using namespace AlibabaCloud::OSS;
static int64_t calculateFolderLength(const OssClient &client, const std::string &bucketName, const std::string &folder)
{
std::string nextMarker = "";
bool isTruncated = false;
int64_t size = 0;
do {
/* 列举文件。*/
ListObjectsRequest request(bucketName);
request.setPrefix(folder);
request.setMarker(nextMarker);
auto outcome = client.ListObjects(request);
if (!outcome.isSuccess()) {
/* 异常处理 */
std::cout << "ListObjects fail" <<
",code:" << outcome.error().Code() <<
",message:" << outcome.error().Message() <<
",requestId:" << outcome.error().RequestId() << std::endl;
break;
}
for (const auto& object : outcome.result().ObjectSummarys()) {
size += object.Size();
}
nextMarker = outcome.result().NextMarker();
isTruncated = outcome.result().IsTruncated();
} while (isTruncated);
return size;
}
int main(void)
{
/* 初始化OSS账号信息。*/
/* yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1(杭州)为例,Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。*/
std::string Endpoint = "yourEndpoint";
/* yourRegion填写Bucket所在地域对应的Region。以华东1(杭州)为例,Region填写为cn-hangzhou。*/
std::string Region = "yourRegion";
/* 填写Bucket名称,例如examplebucket。*/
std::string BucketName = "examplebucket";
/* 填写列举的文件前缀(Prefix)。*/
std::string keyPrefix = "yourkeyPrefix";
/* 初始化网络等资源。*/
InitializeSdk();
ClientConfiguration conf;
conf.signatureVersion = SignatureVersionType::V4;
/* 从环境变量中获取访问凭证。运行本代码示例之前,请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。*/
auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>();
OssClient client(Endpoint, credentialsProvider, conf);
client.SetRegion(Region);
std::string nextMarker = "";
bool isTruncated = false;
do {
/* 列举文件。*/
ListObjectsRequest request(BucketName);
/* 设置正斜线(/)为文件夹的分隔符。*/
request.setDelimiter("/");
request.setPrefix(keyPrefix);
request.setMarker(nextMarker);
auto outcome = client.ListObjects(request);
if (!outcome.isSuccess()) {
/* 异常处理。*/
std::cout << "ListObjects fail" <<
",code:" << outcome.error().Code() <<
",message:" << outcome.error().Message() <<
",requestId:" << outcome.error().RequestId() << std::endl;
break;
}
for (const auto& object : outcome.result().ObjectSummarys()) {
std::cout << "object" <<
",name:" << object.Key() <<
",size:" << object.Size() << std::endl;
}
for (const auto& commonPrefix : outcome.result().CommonPrefixes()) {
int64_t foldersize = calculateFolderLength(client, BucketName, commonPrefix);
std::cout << "folder" <<
",name:" << commonPrefix <<
",size:" << foldersize << std::endl;
}
nextMarker = outcome.result().NextMarker();
isTruncated = outcome.result().IsTruncated();
} while (isTruncated);
/* 释放网络等资源。*/
ShutdownSdk();
return 0;
}
列举指定前缀的文件
以下代码用于列举包含指定前缀(prefix)的文件。
#include <alibabacloud/oss/OssClient.h>
using namespace AlibabaCloud::OSS;
int main(void)
{
/* 初始化OSS账号信息。*/
/* yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1(杭州)为例,Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。*/
std::string Endpoint = "yourEndpoint";
/* yourRegion填写Bucket所在地域对应的Region。以华东1(杭州)为例,Region填写为cn-hangzhou。*/
std::string Region = "yourRegion";
/* 填写Bucket名称,例如examplebucket。*/
std::string BucketName = "examplebucket";
/* 填写列举的文件前缀(Prefix)。*/
std::string keyPrefix = "yourkeyPrefix";
/* 初始化网络等资源。*/
InitializeSdk();
ClientConfiguration conf;
conf.signatureVersion = SignatureVersionType::V4;
/* 从环境变量中获取访问凭证。运行本代码示例之前,请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。*/
auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>();
OssClient client(Endpoint, credentialsProvider, conf);
client.SetRegion(Region);
std::string nextMarker = "";
bool isTruncated = false;
do {
/* 列举文件。*/
ListObjectsRequest request(BucketName);
request.setPrefix(keyPrefix);
request.setMarker(nextMarker);
auto outcome = client.ListObjects(request);
if (!outcome.isSuccess()) {
/* 异常处理。*/
std::cout << "ListObjects fail" <<
",code:" << outcome.error().Code() <<
",message:" << outcome.error().Message() <<
",requestId:" << outcome.error().RequestId() << std::endl;
break;
}
for (const auto& object : outcome.result().ObjectSummarys()) {
std::cout << "object"<<
",name:" << object.Key() <<
",size:" << object.Size() <<
",lastmodify time:" << object.LastModified() << std::endl;
}
nextMarker = outcome.result().NextMarker();
isTruncated = outcome.result().IsTruncated();
} while (isTruncated);
/* 释放网络等资源。*/
ShutdownSdk();
return 0;
}
列举指定marker之后的文件
参数marker代表文件名称。以下代码用于列举指定marker之后的文件。
#include <alibabacloud/oss/OssClient.h>
using namespace AlibabaCloud::OSS;
int main(void)
{
/* 初始化OSS账号信息。*/
/* yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1(杭州)为例,Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。*/
std::string Endpoint = "yourEndpoint";
/* yourRegion填写Bucket所在地域对应的Region。以华东1(杭州)为例,Region填写为cn-hangzhou。*/
std::string Region = "yourRegion";
/* 填写Bucket名称,例如examplebucket。*/
std::string BucketName = "examplebucket";
/* 设置marker。*/
std::string YourMarker = "yourMarker";
/* 初始化网络等资源。*/
InitializeSdk();
ClientConfiguration conf;
conf.signatureVersion = SignatureVersionType::V4;
/* 从环境变量中获取访问凭证。运行本代码示例之前,请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。*/
auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>();
OssClient client(Endpoint, credentialsProvider, conf);
client.SetRegion(Region);
ListObjectOutcome outcome;
do {
/* 列举文件 */
ListObjectsRequest request(BucketName);
/* 列举指定marker之后的文件 */
request.setMarker(YourMarker);
outcome = client.ListObjects(request);
if (!outcome.isSuccess()) {
/* 异常处理 */
std::cout << "ListObjects fail" <<
",code:" << outcome.error().Code() <<
",message:" << outcome.error().Message() <<
",requestId:" << outcome.error().RequestId() << std::endl;
break;
}
YourMarker = outcome.result().NextMarker();
for (const auto& object : outcome.result().ObjectSummarys()) {
std::cout << "object"<<
",name:" << object.Key() <<
",size:" << object.Size() <<
",lastmodify time:" << object.LastModified() << std::endl;
}
} while (outcome.result().IsTruncated());
/* 释放网络等资源 */
ShutdownSdk();
return 0;
}
指定文件名称编码
如果文件名称含有以下特殊字符,需要进行编码传输。OSS目前仅支持URL编码。
单引号('')
双引号("")
and符号(&)
尖括号(< >)
顿号(、)
中文
以下代码用于指定文件名称编码:
#include <alibabacloud/oss/OssClient.h>
using namespace AlibabaCloud::OSS;
int main(void)
{
/* 初始化OSS账号信息。*/
/* yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1(杭州)为例,Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。*/
std::string Endpoint = "yourEndpoint";
/* yourRegion填写Bucket所在地域对应的Region。以华东1(杭州)为例,Region填写为cn-hangzhou。*/
std::string Region = "yourRegion";
/* 填写Bucket名称,例如examplebucket。*/
std::string BucketName = "examplebucket";
/* 初始化网络等资源 */
InitializeSdk();
ClientConfiguration conf;
conf.signatureVersion = SignatureVersionType::V4;
/* 从环境变量中获取访问凭证。运行本代码示例之前,请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。*/
auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>();
OssClient client(Endpoint, credentialsProvider, conf);
client.SetRegion(Region);
std::string nextMarker = "";
bool isTruncated = false;
do {
/* 列举文件。*/
ListObjectsRequest request(BucketName) ;
/* 指定文件名称编码。*/
request.setEncodingType("url");
request.setMarker(nextMarker);
auto outcome = client.ListObjects(request);
if (!outcome.isSuccess() ) {
/* 异常处理。*/
std::cout << "ListObjects fail" <<
",code:" << outcome.error().Code() <<
",message:" << outcome.error().Message() <<
",requestId:" << outcome.error().RequestId() << std::endl;
break;
}
for (const auto& object : outcome.result().ObjectSummarys()) {
std::cout << "object"<<
",name:" << object.Key() <<
",size:" << object.Size() <<
",lastmodify time:" << object.LastModified() << std::endl;
}
nextMarker = outcome.result().NextMarker();
isTruncated = outcome.result().IsTruncated();
} while (isTruncated);
/* 释放网络等资源。*/
ShutdownSdk();
return 0;
}
文件夹功能
OSS没有文件夹的概念,所有元素都是以文件来存储。创建文件夹本质上来说是创建了一个大小为0并以正斜线(/)结尾的文件。这个文件可以被上传和下载,控制台会对以正斜线(/)结尾的文件以文件夹的方式展示。
通过delimiter和prefix两个参数可以模拟文件夹功能:
如果设置prefix为某个文件夹名称,则会列举以此prefix开头的文件,即该文件夹下所有的文件和子文件夹(目录)均显示为objects。
如果在设置了prefix的情况下,将delimiter设置为正斜线(/),则只列举该文件夹下的文件和子文件夹(目录),该文件夹下的子文件夹(目录)显示为CommonPrefixes,子文件夹下的文件和文件夹不显示。
假设存储空间中包含文件oss.jpg
、fun/test.jpg
、fun/movie/001.avi
和fun/movie/007.avi
,以正斜线(/)作为文件夹的分隔符。以下示例说明了如何通过模拟文件夹的方式列举文件。
列举存储空间下所有文件
以下代码用于列举指定存储空间下的所有文件。
#include <alibabacloud/oss/OssClient.h> using namespace AlibabaCloud::OSS; int main(void) { /* 初始化OSS账号信息。*/ /* yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1(杭州)为例,Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。*/ std::string Endpoint = "yourEndpoint"; /* yourRegion填写Bucket所在地域对应的Region。以华东1(杭州)为例,Region填写为cn-hangzhou。*/ std::string Region = "yourRegion"; /* 填写Bucket名称,例如examplebucket。*/ std::string BucketName = "examplebucket"; /* 初始化网络等资源。*/ InitializeSdk(); ClientConfiguration conf; conf.signatureVersion = SignatureVersionType::V4; /* 从环境变量中获取访问凭证。运行本代码示例之前,请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。*/ auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>(); OssClient client(Endpoint, credentialsProvider, conf); client.SetRegion(Region); std::string nextMarker = ""; bool isTruncated = false; do { /* 列举文件。*/ ListObjectsRequest request(BucketName); request.setMarker(nextMarker); auto outcome = client.ListObjects(request); if (!outcome.isSuccess()) { /* 异常处理。*/ std::cout << "ListObjects fail" << ",code:" << outcome.error().Code() << ",message:" << outcome.error().Message() << ",requestId:" << outcome.error().RequestId() << std::endl; ShutdownSdk(); return -1; } else { for (const auto& object : outcome.result().ObjectSummarys()) { std::cout << "object"<< ",name:" << object.Key() << ",size:" << object.Size() << ",lastmodify time:" << object.LastModified() << std::endl; } } nextMarker = outcome.result().NextMarker(); isTruncated = outcome.result().IsTruncated(); } while (isTruncated); /* 释放网络等资源。*/ ShutdownSdk(); return 0; }
返回结果如下:
Objects: fun/movie/001.avi fun/movie/007.avi fun/test.jpg oss.jpg CommonPrefixes:
列举指定目录下所有文件
以下代码用于列举指定目录下的所有文件。
#include <alibabacloud/oss/OssClient.h> using namespace AlibabaCloud::OSS; int main(void) { /* 初始化OSS账号信息。*/ /* yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1(杭州)为例,Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。*/ std::string Endpoint = "yourEndpoint"; /* yourRegion填写Bucket所在地域对应的Region。以华东1(杭州)为例,Region填写为cn-hangzhou。*/ std::string Region = "yourRegion"; /* 填写Bucket名称,例如examplebucket。*/ std::string BucketName = "examplebucket"; /* 初始化网络等资源。*/ InitializeSdk(); ClientConfiguration conf; conf.signatureVersion = SignatureVersionType::V4; /* 从环境变量中获取访问凭证。运行本代码示例之前,请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。*/ auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>(); OssClient client(Endpoint, credentialsProvider, conf); client.SetRegion(Region); std::string nextMarker = ""; bool isTruncated = false; do { /* 列举文件。*/ ListObjectsRequest request(BucketName); request.setPrefix("fun/"); request.setMarker(nextMarker); auto outcome = client.ListObjects(request); if (!outcome.isSuccess()) { /* 异常处理。*/ std::cout << "ListObjects fail" << ",code:" << outcome.error().Code() << ",message:" << outcome.error().Message() << ",requestId:" << outcome.error().RequestId() << std::endl; break; } for (const auto& object : outcome.result().ObjectSummarys()) { std::cout << "object"<< ",name:" << object.Key() << ",size:" << object.Size() << ",lastmodify time:" << object.LastModified() << std::endl; } for (const auto& commonPrefix : outcome.result().CommonPrefixes()) { std::cout << "commonPrefix" << ",name:" << commonPrefix << std::endl; } nextMarker = outcome.result().NextMarker(); isTruncated = outcome.result().IsTruncated(); } while (isTruncated); /* 释放网络等资源。*/ ShutdownSdk(); return 0; }
返回结果如下:
Objects: fun/movie/001.avi fun/movie/007.avi fun/test.jpg CommonPrefixes:
列举目录下的文件和子目录
以下代码用于列举指定目录下的文件和子目录。
#include <alibabacloud/oss/OssClient.h> using namespace AlibabaCloud::OSS; int main(void) { /* 初始化OSS账号信息。*/ /* yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1(杭州)为例,Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。*/ std::string Endpoint = "yourEndpoint"; /* yourRegion填写Bucket所在地域对应的Region。以华东1(杭州)为例,Region填写为cn-hangzhou。*/ std::string Region = "yourRegion"; /* 填写Bucket名称,例如examplebucket。*/ std::string BucketName = "examplebucket"; /* 初始化网络等资源。*/ InitializeSdk(); ClientConfiguration conf; conf.signatureVersion = SignatureVersionType::V4; /* 从环境变量中获取访问凭证。运行本代码示例之前,请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。*/ auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>(); OssClient client(Endpoint, credentialsProvider, conf); client.SetRegion(Region); std::string nextMarker = ""; bool isTruncated = false; do { /* 列举文件。*/ ListObjectsRequest request(BucketName); /* 设置正斜线(/)为文件夹的分隔符 */ request.setDelimiter("/"); request.setPrefix("fun/"); request.setMarker(nextMarker); auto outcome = client.ListObjects(request); if (!outcome.isSuccess()) { /* 异常处理。*/ std::cout << "ListObjects fail" << ",code:" << outcome.error().Code() << ",message:" << outcome.error().Message() << ",requestId:" << outcome.error().RequestId() << std::endl; break; } for (const auto& object : outcome.result().ObjectSummarys()) { std::cout << "object"<< ",name:" << object.Key() << ",size:" << object.Size() << ",lastmodify time:" << object.LastModified() << std::endl; } for (const auto& commonPrefix : outcome.result().CommonPrefixes()) { std::cout << "commonPrefix" << ",name:" << commonPrefix << std::endl; } nextMarker = outcome.result().NextMarker(); isTruncated = outcome.result().IsTruncated(); } while (isTruncated); /* 释放网络等资源。*/ ShutdownSdk(); return 0; }
返回结果如下:
Objects: fun/test.jpg CommonPrefixes: fun/movie/
列举指定目录下的文件大小
以下代码用于获取指定目录下的文件大小:
#include <alibabacloud/oss/OssClient.h> using namespace AlibabaCloud::OSS; static int64_t calculateFolderLength (const OssClient &client, const std::string &bucketName, const std::string &folder) { std::string nextMarker = ""; bool isTruncated = false; int64_t size = 0; do { /* 列举文件。*/ ListObjectsRequest request(bucketName); request.setPrefix(folder); request.setMarker(nextMarker); auto outcome = client.ListObjects(request); if (!outcome.isSuccess()) { /* 异常处理。*/ std::cout << "ListObjects fail" << ",code:" << outcome.error().Code() << ",message:" << outcome.error().Message() << ",requestId:" << outcome.error().RequestId() << std::endl; break; } for (const auto& object : outcome.result().ObjectSummarys()) { size += object.Size(); } nextMarker = outcome.result().NextMarker(); isTruncated = outcome.result().IsTruncated(); } while (isTruncated); return size; } int main(void) { /* 初始化OSS账号信息。*/ /* yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1(杭州)为例,Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。*/ std::string Endpoint = "yourEndpoint"; /* yourRegion填写Bucket所在地域对应的Region。以华东1(杭州)为例,Region填写为cn-hangzhou。*/ std::string Region = "yourRegion"; /* 填写Bucket名称,例如examplebucket。*/ std::string BucketName = "examplebucket"; /* 初始化网络等资源 */ InitializeSdk(); ClientConfiguration conf; conf.signatureVersion = SignatureVersionType::V4; /* 从环境变量中获取访问凭证。运行本代码示例之前,请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。*/ auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>(); OssClient client(Endpoint, credentialsProvider, conf); client.SetRegion(Region); std::string nextMarker = ""; bool isTruncated = false; do { /* 列举文件。*/ ListObjectsRequest request(BucketName); /* 设置正斜线(/)为文件夹的分隔符。*/ request.setDelimiter("/"); request.setPrefix("fun/"); request.setMarker(nextMarker); auto outcome = client.ListObjects(request); if (!outcome.isSuccess()) { /* 异常处理。*/ std::cout << "ListObjects fail" << ",code:" << outcome.error().Code() << ",message:" << outcome.error().Message() << ",requestId:" << outcome.error().RequestId() << std::endl; break; } for (const auto& object : outcome.result().ObjectSummarys()) { std::cout << "object" << ",name:" << object.Key() << ",size:" << object.Size() << std::endl; } for (const auto& commonPrefix : outcome.result().CommonPrefixes()) { int64_t foldersize = calculateFolderLength(client, BucketName, commonPrefix); std::cout << "folder" << ",name:" << commonPrefix << ",size:" << foldersize << std::endl; } nextMarker = outcome.result().NextMarker(); isTruncated = outcome.result().IsTruncated(); } while (isTruncated); /* 释放网络等资源。*/ ShutdownSdk(); return 0; }
相关文档
关于列举文件的完整示例代码,请参见GitHub示例。
关于列举文件的API接口说明,请参见GetBucket (ListObjects)和ListObjectsV2(GetBucketV2)。