linQ 到 lambda 的翻译在 linQpad4 中不起作用

Question

我第一次使用 LinQPad4。我在程序中运行了一个 LinQ 查询示例，当我按下 Lambda 底部时，程序没有显示转换为 Lambda 的查询，有人可以帮我吗？

var words = from word in "The quick brown fox jumps over the lazy dog".Split() 
            orderby word.ToUpper() 
            select word; 
var duplicates = from word in words 
                 group word.ToUpper() by word.ToUpper() 
                 into g 
                 where g.Count() > 1 
                 select new { g.Key, Count = g.Count() };
words.Dump(); 
duplicates.Dump();

Answer 1

如果是本地查询，则需要插入.AsQueryable()查询以生成表达式树。这在内置示例中进行了解释，A Note on AsQueryable

var names = new[] { "Tom", "Dick", "Harry", "Mary", "Jay" }.AsQueryable();

// AsQueryable() doesn't change the result of the query. The effect it has it to populate 
// the ? tab below—so you can see how the query translates into lambda (fluent) syntax.
// To illustrate, press F5 to run the following:
(
    from n in names
    where n.Length > 3
    orderby n descending
    select n.ToUpper()
)
.Dump ("Click the ? button - notice the translation to fluent syntax");