/// <summary> /// Adds the values as a join string, if it is not null or empty. /// </summary> /// <param name="plist">The list.</param> /// <param name="key">The key.</param> /// <param name="separator">The separator.</param> /// <param name="values">The values.</param> public static void AddIfNotNullOrEmpty(this PList plist, string key, string separator, IEnumerable <string>?values) { if (values is null) { return; } plist.AddIfNotNullOrEmpty(key, string.Join(separator, values)); }