下面的第二個測試方法不能編譯(不能將lambda表達式轉換爲目標類型D1)。這是否意味着(非泛型)委託逆轉不適用於lambda表達式? [TestFixture]
public class MyVarianceTests
{
private abstract class Animal {}
private class Tiger : Animal {}
priv
下面調用重載Enumerable.Select方法: var itemOnlyOneTuples = "test".Select<char, Tuple<char>>(Tuple.Create);
失敗的歧義錯誤(命名空間爲清楚起見移除): The call is ambiguous between the following methods or properties:
'Enumerab
我想在Linq中調用一個簡單的方法組,但我收到此錯誤。 The call is ambiguous between the following methods or properties: 'System.Linq.Enumerable.Select<string,int>(System.Collections.Generic.IEnumerable<string>, System.Func<st