NuGet.PackageReferenceFile.AddEntry C# (CSharp) Method

        private void AddEntry(XDocument document, string id, SemanticVersion version, FrameworkName targetFramework)
        {
            XElement element = FindEntry(document, id, version);

            if (element != null)
            {
                element.Remove();
            }

            var newElement = new XElement("package",
                                  new XAttribute("id", id),
                                  new XAttribute("version", version));
            if (targetFramework != null)
            {
                newElement.Add(new XAttribute("targetFramework", VersionUtility.GetShortFrameworkName(targetFramework)));
            }

            // Restore the version constraint
            string versionConstraint;
            if (_constraints.TryGetValue(id, out versionConstraint))
            {
                newElement.Add(new XAttribute("allowedVersions", versionConstraint));
            }

            document.Root.Add(newElement);

            SaveDocument(document);
        }

 public void AddPackageReferenceEntry(string packageId, SemanticVersion version)
 {
     if (_packageReferenceFile != null)
     {
         _packageReferenceFile.AddEntry(packageId, version);
     }
 }