annotations/Azaion.Common/Extensions/DirectoryInfoExtensions.cs

using System.IO;

namespace Azaion.Common.Extensions;

public static class DirectoryInfoExtensions
{
    public static IEnumerable<FileInfo> GetFiles(this DirectoryInfo dir, params string[] searchExtensions) =>
        dir.GetFiles("*.*", SearchOption.AllDirectories)
            .Where(f => searchExtensions.Any(s => f.Name.ToLower().Contains(s))).ToList();
}