NuGet.PackageReferenceFile.GetDocument C# (CSharp) Method

        private XDocument GetDocument(bool createIfNotExists = false)
        {
            try
            {
                // If the file exists then open and return it
                if (FileSystem.FileExists(_path))
                {
                    using (Stream stream = FileSystem.OpenFile(_path))
                    {
                        return XDocument.Load(stream);
                    }
                }

                // If it doesn't exist and we're creating a new file then return a
                // document with an empty packages node
                if (createIfNotExists)
                {
                    return new XDocument(new XElement("packages"));
                }

                return null;
            }
            catch (XmlException e)
            {
                throw new InvalidOperationException(
                    String.Format(CultureInfo.CurrentCulture, NuGetResources.ErrorReadingFile, FileSystem.GetFullPath(_path)), e);
            }
        }
    }