我有一个这样的课:
class MyClass<T> {
public string value1 { get; set; }
public T objT { get; set; }
}
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以及这个班级的清单.我想使用.net 3.5 lambda或linq来获取不同value1的MyClass列表.我想这可能比在.net 2.0中缓存这样的列表的方式简单得多:
List<MyClass<T>> list;
...
List<MyClass<T>> listDistinct = new List<MyClass<T>>();
foreach (MyClass<T> instance in list)
{
// some code to check if listDistinct does contain obj with intance.Value1
// then listDistinct.Add(instance);
}
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lambda或LINQ的做法是什么?
我需要通过ID获得唯一的PostViewModel.这与lambda表达有什么关系?
public IEnumerable<PostViewModel> DistinctPosts
{
get
{
return Employees
.SelectMany(e => e.PostList.Posts)
.Distinct(new PostViewModelComparer())
.ToList();
}
}
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比较器:
class PostViewModelComparer : IEqualityComparer<PostViewModel>
{
#region IEqualityComparer<Contact> Members
public bool Equals(PostViewModel x, PostViewModel y)
{
return x.ID.Equals(y.ID);
}
public int GetHashCode(PostViewModel obj)
{
return obj.ID.GetHashCode();
}
#endregion
}
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抱歉,对于LINQ的Distinct()使用委托进行相等比较,这是一个很好的例子.
当我需要比较2个列表并生成包含所有唯一项目的第3个列表时,我似乎总是遇到问题.我需要经常执行此操作.
尝试用一个简单的例子重现这个问题.
我错过了什么吗?谢谢你的任何建议
想要的结果
Name= Jo1 Surname= Bloggs1 Category= Account
Name= Jo2 Surname= Bloggs2 Category= Sales
Name= Jo5 Surname= Bloggs5 Category= Development
Name= Jo6 Surname= Bloggs6 Category= Management
Name= Jo8 Surname= Bloggs8 Category= HR
Name= Jo7 Surname= Bloggs7 Category= Cleaning
class Program
{
static void Main(string[] args)
{
List<Customer> listOne = new List<Customer>();
List<Customer> listTwo = new List<Customer>();
listOne.Add(new Customer { Category = "Account", Name = "Jo1", Surname = "Bloggs1" });
listOne.Add(new Customer { Category = "Sales", Name = "Jo2", …Run Code Online (Sandbox Code Playgroud)