您可以使用列表来保存所需的所有扩展名，并使用

You can use a list to save all the extension that you need and use Contains extension method in your query:

var list=new List<string>(){".dll", ".exe"};
var libraries = myDynamicList.Where(d => list.Contains(Path.GetExtension(d.FileName)))
                             .Select(d => d.FileName);

您还可以使用 Any 扩展方法:

You can also use Any extension method:

 var libraries = myDynamicList.Where(d => list.Any(e=>e==Path.GetExtension(d.FileName)))
                              .Select(d => d.FileName);