Entity PrimaryKey using Metadata Service

Sometimes we need to get the Entity ID for the any custom entity, by default the entityid equals to +"id". So we can get the id for any dynamic entity as

Entity.Properties["entitylogicalname"+"id"];

But this is a snippet for achieving the same using metadata service.

// Get the Primary key from CRM Entity
        public string GetEntityPrimaryKey(String EntityName)
        {
            // Metadata Service
            Func myMetaService = () =>
            {
                // Create an authentication token.
                CrmAuthenticationToken token = new CrmAuthenticationToken();
                token.OrganizationName = "OrgName";
                token.AuthenticationType = 0;

                // Create the metadata Web service;
                MetadataService metadataService = new MetadataService();
                metadataService.Url = "http://:/MSCRMServices/2007/MetadataService.asmx";
                metadataService.CrmAuthenticationTokenValue = token;
                metadataService.Credentials = System.Net.CredentialCache.DefaultCredentials;
                metadataService.PreAuthenticate = true;
                return metadataService;
            };

            // Create the request
            RetrieveEntityRequest entityRequest = new RetrieveEntityRequest();
            entityRequest.RetrieveAsIfPublished = false;
            entityRequest.LogicalName = EntityName;
            entityRequest.EntityItems = EntityItems.EntityOnly;

            // Execute the request
            RetrieveEntityResponse entityResponse = (RetrieveEntityResponse)myMetaService().Execute(entityRequest);

            // Access the retrieved entity
            EntityMetadata retrievedEntityMetadata = entityResponse.EntityMetadata;
            return retrievedEntityMetadata.PrimaryKey;
        }