Overview

This document provides an overview of APIs and SDK code samples related to querying object metadata.

SDK API References

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

Querying Object Metadata

Description

This API is used to query the metadata of an object, including custom headers and ETag.

Sample code

using COSXML.Model.Object;
using COSXML.Auth;
using System;
using COSXML;
namespace COSSnippet
{
   public class HeadObjectModel {
      private CosXml cosXml;
      HeadObjectModel() {
       CosXmlConfig config = new CosXmlConfig.Builder()
         .SetRegion("COS_REGION") // Set the default region. For abbreviations of COS regions, visit https://intl.cloud.tencent.com/document/product/436/6224?from_cn_redirect=1.
         .Build();

       string secretId = "SECRET_ID";   // SecretId of the TencentCloud API. For more information about how to obtain the API key, see https://console.cloud.tencent.com/cam/capi.
       string secretKey = "SECRET_KEY"; // SecretKey of the TencentCloud API. For more information about how to obtain the API key, see https://console.cloud.tencent.com/cam/capi.
       long durationSecond = 600;          // Validity period of the request signature in seconds
       QCloudCredentialProvider qCloudCredentialProvider = new DefaultQCloudCredentialProvider(secretId, 
         secretKey, durationSecond);

       this.cosXml = new CosXmlServer(config, qCloudCredentialProvider);
     }
      /// Obtain object information
     public void HeadObject()
     {
       //.cssg-snippet-body-start:[head-object]
       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";
         string key = "exampleobject"; // Object key
         HeadObjectRequest request = new HeadObjectRequest(bucket, key);
         // Execute the request
         HeadObjectResult result = cosXml.HeadObject(request);
         // Request succeeded
         Console.WriteLine(result.GetResultInfo());
         // Print CRC64 value of the object
         Console.WriteLine(result.crc64ecma);
         // Print ETag of the object
         Console.WriteLine(result.eTag);
       }
       catch (COSXML.CosException.CosClientException clientEx)
       {
         // Request failed
         Console.WriteLine("CosClientException: " + clientEx);
       }
       catch (COSXML.CosException.CosServerException serverEx)
       {
         // Request failed
         Console.WriteLine("CosServerException: " + serverEx.GetInfo());
       }

       //.cssg-snippet-body-end
     }
     // .cssg-methods-pragma
      static void Main(string[] args)
     {
       HeadObjectModel m = new HeadObjectModel();
        /// Obtain object information
       m.HeadObject();
       // .cssg-methods-pragma
     }
   }
}

Note：

For the complete sample, go to GitHub.