System.IO.Packaging.PackUriHelper.IsRelationshipPartUri C# (CSharp) Méthode

        public static bool IsRelationshipPartUri(Uri partUri)
        {
            Check.PartUri(partUri);
            return partUri.OriginalString.StartsWith("/_rels") && partUri.OriginalString.EndsWith(".rels");
        }

        /// <summary>
        /// Protected constructor for the abstract Base class.
        /// This is the current contract between the subclass and the base class
        /// If we decide some registration mechanism then this might change
        ///
        /// NOTE : If you are using this constructor from your subclass or passing a null
        /// for the content type parameter, be sure to implement the GetContentTypeCore
        /// method, as that will be called to get the content type value. This is provided
        /// to enable lazy initialization of the ContentType property.
        ///
        /// </summary>
        /// <param name="package">Package in which this part is being created</param>
        /// <param name="partUri">uri of the part</param>
        /// <param name="contentType">Content Type of the part, can be null if the value
        /// is unknown at the time of construction. However the value has to be made
        /// available anytime the ContentType property is called. A null value only indicates
        /// that the value will be provided later. Every PackagePart must have a valid
        /// Content Type</param>
        /// <param name="compressionOption">compression option for this part</param>
        /// <exception cref="ArgumentNullException">If parameter "package" is null</exception>
        /// <exception cref="ArgumentNullException">If parameter "partUri" is null</exception>
        /// <exception cref="ArgumentOutOfRangeException">If CompressionOption enumeration [compressionOption] does not have one of the valid values</exception>
        /// <exception cref="ArgumentException">If parameter "partUri" does not conform to the valid partUri syntax</exception>
        protected PackagePart(Package package,
                              Uri partUri,
                              string contentType,
                              CompressionOption compressionOption)
        {
            if (package == null)
            {
                throw new ArgumentNullException("package");
            }

            if (partUri == null)
            {
                throw new ArgumentNullException("partUri");
            }

            Package.ThrowIfCompressionOptionInvalid(compressionOption);

            _uri       = PackUriHelper.ValidatePartUri(partUri);
            _container = package;

            if (contentType == null)
            {
                _contentType = null;
            }
            else
            {
                _contentType = new ContentType(contentType);
            }

            _requestedStreams   = null;
            _compressionOption  = compressionOption;
            _isRelationshipPart = PackUriHelper.IsRelationshipPartUri(partUri);
        }