public ActionResult Index()

{

IList<RegisterModel> regList = new List<RegisterModel>()

{

new RegisterModel{ UserName ="zhangsan", Password="123456", ConfirmPassword ="123456"},

new RegisterModel{ UserName ="li", Password="123456", ConfirmPassword ="123456"},

new RegisterModel{ UserName ="zhangsan", Password="123456", ConfirmPassword ="123456"},

new RegisterModel{ UserName ="wangwu", Password="123456", ConfirmPassword ="123456"},

new RegisterModel{ UserName ="zhangsan", Password="123456", ConfirmPassword ="123456"}

};

List<RegisterModel> lambdaList = regList.Distinct(new Compare<RegisterModel>(

(x, y) => (null != x && null != y) && (x.UserName == y.UserName))).ToList();

return View();

}

public delegate bool EqualsComparer<T>(T x, T y);

public class Compare<T> : IEqualityComparer<T>

{

private EqualsComparer<T> _equalsComparer;

public Compare(EqualsComparer<T> equalsComparer)

{

this._equalsComparer = equalsComparer;

}

public bool Equals(T x, T y)

{

if (null != this._equalsComparer)

return this._equalsComparer(x, y);

else

return false;

}

public int GetHashCode(T obj)

{

return obj.ToString().GetHashCode();

}

}

//******************************

var linqlist = (from r in regList

group r by r.UserName into g

select g).ToList();

foreach (var group in linqlist)

{

// 输出组内成员

foreach (var score in group)

{

Console.WriteLine(score);

}

}