我有一个项目列表,我正在努力获得独特的记录,
有些记录没有Id(0),有些记录有Id,是否可以获取带有Id的记录?
void Main() {
var a = new Skill {Id =0, Name="test"};
var b = new Skill {Id =0, Name="test"};
var c = new Skill {Id= 1, Name="test" }; // masterlist skill
var listA = new List<Skill> { a, b };
var listB = new List<Skill> { c };
var result = listA.Union(listB, new SkillComparer());
result.Dump();
}
public class SkillComparer : IEqualityComparer<Skill>
{
#region IEqualityComparer<Skill> Members
public bool Equals(Skill skill, Skill skillToCompare)
{
return skill.Name == skillToCompare.Name;
}
public int GetHashCode(Skill obj)
{
return obj.Name.GetHashCode();
}
#endregion
}
public class Skill {
public int Id {get;set;}
public string Name {get;set;}
结果
ID:0 | Name: Test
有没有办法返回materlist的id?
ID:1 | Name: Test
答案 0 :(得分:1)
使用linq:
var result = listA.Concat(listB).OrderByDescending(s => s.Id).Distinct(new SkillComparer());
这会产生一个不同的技能名单列表,每个名单都包含其名称的最大ID。
var a = new Skill {Id =0, Name="test"};
var b = new Skill {Id =2, Name="test"};
var c = new Skill {Id= 1, Name="test" };
var d = new Skill { Id = 3, Name = "foo" };
var e = new Skill { Id = 0, Name = "foo" };
var listA = new List<Skill> { a, b };
var listB = new List<Skill> { c, d, e };
var result = listA.Concat(listB).OrderByDescending(s => s.Id).Distinct(new SkillComparer());
foreach (var skill in result)
{
Console.WriteLine(string.Format("{0}: {1}", skill.Name, skill.Id));
}
结果:
foo: 3
test: 2
答案 1 :(得分:1)
有更有效的方法,但据我所知的问题:
listA.AddRange(listB).Where(o => o.Name == desiredName).Max(o => o.Id);