CloudMusic/FNZCM/FNZCM.BlazorWasm/Utility/ExtenstionMetohd.cs

namespace FNZCM.BlazorWasm.Utility
{
    public static class ExtenstionMetohd
    {
        public static IEnumerable<(T item, int index)> WithIndex<T>(this IEnumerable<T> self)
            => self.Select((item, index) => (item, index));

        public static TV GetEx<TK, TV>(this IDictionary<TK, TV> dic, TK key)
        {
            if (key == null) return default;
            return dic.TryGetValue(key, out var tv)
                ? tv
                : default;
        }

        public static IReadOnlyCollection<T> KeepNoEmpty<T>(this IReadOnlyCollection<T> source)
        {
            if (source == null) return new T[1];
            if (source.Count == 0) return new T[1];
            return source;
        }
    }
}