public IQueryable <Book> GetBooks(string title, string author, string isbn)
{
var query = ReadData.AsQueryable();
if (!string.IsNullOrEmpty(title))
{
query = query.Where(x => x.title == title).AsQueryable();
}
if (!string.IsNullOrEmpty(author))
{
query = query.Where(x => x.author == author).AsQueryable();
}
if (!string.IsNullOrEmpty(isbn))
{
query = query.Where(x => x.isbn == isbn).AsQueryable();
}
return(query);
}
public IQueryable <Book> GetBook() => ReadData.AsQueryable();
