我有一个员工类
public class Employee
{
public int ID { get; set; }
public string Name { get; set; }
public string Age { get; set; }
public string Address { get; set; }
public string ContactNo { get; set; }
}
并有填充方法填写清单
private static void FillEmployeeList(ref List<Employee> lt1, ref List<Employee> lt2)
{
lt1 = new List<Employee> {new Employee{ID=1,Name="Kavya",Age="24",Address="No.1,Nehru Street,Chennai",ContactNo="9874521456"},
new Employee{ID=2,Name="Ravi",Age="24",Address="Flat No.25/A1,Gandhi Street,Chennai",ContactNo="9658745258"},
new Employee{ID=3,Name="Lavnya",Age="30",Address="No.12,Shastri nagar,Chennai",ContactNo="5214587896"},
new Employee{ID=4,Name="Rupa",Age="31",Address="No.23/5,Nehru Street,Chennai",ContactNo="9874521256"},
new Employee{ID=5,Name="Divya",Age="32",Address="No.1/227,Nehru Street,Chennai",ContactNo="8541256387"},
};
lt2 = new List<Employee> {new Employee{ID=1,Name="Kavya",Age="24",Address="No.1,Nehru Street,Chennai",ContactNo="9874521456"},
new Employee{ID=2,Name="Ravindran",Age="30",Address="Flat No.25/A1,Gandhi Street,Chennai",ContactNo="9658745258"},
new Employee{ID=3,Name="Chandru",Age="30",Address="No.12,Shastri nagar,Chennai",ContactNo="5214587896"},
new Employee{ID=4,Name="Rakesh",Age="32",Address="No.23/5,Nehru Street,Chennai",ContactNo="9874021256"},
new Employee{ID=5,Name="Suresh",Age="32",Address="No.1/227,Nehru Street,Chennai",ContactNo="8541056387"},
new Employee{ID=11,Name="Suryakala",Age="28",Address="No.1,Pillayar koil Street,Chennai",ContactNo="9541204782"},
new Employee{ID=12,Name="Thivya",Age="41",Address="No.42,Ellaiamman koil Street,Chennai",ContactNo="9632140874"},
};
}
比较两个对象列表
protected List<Employee> ListCompare(List<Employee> lt1, List<Employee> lt2)
{
FillEmployeeList(ref lt1, ref lt2);
List<Employee> lst = new List<Employee>();
if (lt1.Count > 0 && lt2.Count > 0)
{
// Displaying Matching Records from List1 and List2 by ID
var result = (from l1 in lt1
join l2 in lt2
on l1.ID equals l2.ID
orderby l1.ID
select new
{
ID = l1.ID,
Name = (l1.Name == l2.Name) ? "$" : (l2.Name + " (Modified)"),
Age = (l1.Age == l2.Age) ? "$" : (l2.Age + " (Modified)"),
Address = (l1.Address == l2.Address) ? "$" : (l2.Address + " (Modified)"),
ContactNo = (l1.ContactNo == l2.ContactNo) ? "$" : (l2.ContactNo + " (Modified)")
}).ToList();
// Displaying Records from List1 which is not in List2
var result1 = from l1 in lt1
where !(from l2 in lt2
select l2.ID).Contains(l1.ID)
orderby l1.ID
select new
{
ID = l1.ID,
Name = " Deleted",
Age = " Deleted",
Address = " Deleted",
ContactNo = " Deleted"
};
// Displaying Records from List1 which is not in List2
var result2 = from l1 in lt2
where !(from l2 in lt1
select l2.ID).Contains(l1.ID)
orderby l1.ID
select new
{
ID = l1.ID,
Name = l1.Name + " (Added)",
Age = l1.Age + " (Added)",
Address = l1.Address + " (Added)",
ContactNo = l1.ContactNo + " (Added)"
};
var res1 = result.Concat(result1).Concat(result2);
foreach (var item in res1)
{
Employee emp = new Employee();
//Response.Write(item + "<br/>");
emp.ID = item.ID;
emp.Name = item.Name;
emp.Age = item.Age;
emp.Address = item.Address;
emp.ContactNo = item.ContactNo;
lst.Add(emp);
}
}
return lst;
}
这里我调用compareList方法并返回结果并将其显示在html表中。
List<Employee> lt1 = new List<Employee>();
List<Employee> lt2 = new List<Employee>();
List<Employee> resultset = new List<Employee>();
//string value = "ID";
StringBuilder htmlTable = new StringBuilder();
htmlTable.Append("<table border='1'>");
htmlTable.Append("<tr><th>ID</th><th>Name</th><th>Age</th><th>Address</th><th>ContactNo</th></tr>");
resultset = ListCompare(lt1, lt2);
foreach(var item in resultset)
{
htmlTable.Append("<tr>");
htmlTable.Append("<td>" + item.ID + "</td>");
htmlTable.Append("<td>" + item.Name + "</td>");
htmlTable.Append("<td>" + item.Age + "</td>");
htmlTable.Append("<td>" + item.Address + "</td>");
htmlTable.Append("<td>" + item.ContactNo + "</td>");
htmlTable.Append("</tr>");
}
htmlTable.Append("</table>");
PlaceHolder1.Controls.Add(new Literal { Text = htmlTable.ToString() });
我的问题是如何推广这种编码。我可能有任何课程（如员工或学生）。我想要编码只是我将两个对象列表传递给CompareMethod（比较方法我将传递任何类型的对象列表），这将返回列表作为结果。如何进行，请给出任何想法。
答案 0 :(得分：0)
您可以按以下方式创建比较方法：
protected List<TResult> ListCompare<TKey, TInput, TResult>(List<TInput> lt1, List<TInput> lt2, Func<TInput, TKey> key, Func<TInput, TInput, TResult> modified, Func<TInput, TResult> added, Func<TInput, TResult> deleted)
{
// Displaying Matching Records from List1 and List2 by ID
var matchingEmployees = lt1.Join(lt2, key, key, modified);
// Displaying Records from List1 which is not in List2
var lt1NotInlt2 = lt1
.Where(e1 => !lt2.Any(e2 => key(e2).Equals(key(e1))))
.Select(deleted);
// Displaying Records from List2 which is not in List1
var lt2NotInlt1 = lt2
.Where(e2 => !lt1.Any(e1 => key(e1).Equals(key(e2))))
.Select(added);
return matchingEmployees.Concat(lt1NotInlt2).Concat(lt2NotInlt1).ToList();
}
如果您不想使用密钥，那么您的比较方法应该如下所示，您的类应该实现Equals方法：
protected List<TResult> ListCompare<TInput, TResult>(List<TInput> lt1, List<TInput> lt2, Func<TInput, TInput, TResult> modified, Func<TInput, TResult> added, Func<TInput, TResult> deleted)
{
// Displaying Matching Records from List1 and List2 by ID
var matchingEmployees = lt1
.Where(e1 => lt2.Any(e2 => e2.Equals(e1)))
.Select(e1 =>
{
var e2 = lt2.First(e => e.Equals(e1));
return modified(e1, e2);
});
// Displaying Records from List1 which is not in List2
var lt1NotInlt2 = lt1
.Where(e1 => !lt2.Any(e2 => e2.Equals(e1)))
.Select(deleted);
// Displaying Records from List2 which is not in List1
var lt2NotInlt1 = lt2
.Where(e2 => !lt1.Any(e1 => e1.Equals(e2)))
.Select(added);
return matchingEmployees.Concat(lt1NotInlt2).Concat(lt2NotInlt1).ToList();
}
然后你可以像这样调用比较方法：
var result = ListCompare<int, Employee, Employee>(
lt1,
lt2,
e => e.ID,
(e1, e2) => new Employee
{
ID = e1.ID,
Name = (e1.Name == e2.Name) ? "$" : (e2.Name + " (Modified)"),
Age = (e1.Age == e2.Age) ? "$" : (e2.Age + " (Modified)"),
Address = (e1.Address == e2.Address) ? "$" : (e2.Address + " (Modified)"),
ContactNo = (e1.ContactNo == e2.ContactNo) ? "$" : (e2.ContactNo + " (Modified)")
},
e => new Employee
{
ID = e.ID,
Name = e.Name + " (Added)",
Age = e.Age + " (Added)",
Address = e.Address + " (Added)",
ContactNo = e.ContactNo + " (Added)"
},
e => new Employee
{
ID = e.ID,
Name = " Deleted",
Age = " Deleted",
Address = " Deleted",
ContactNo = " Deleted"
});
答案 1 :(得分：0)
如果你对收藏平等感兴趣，我想建议下一步：
通过使用指定的IEqualityComparer比较它们的元素来确定两个序列是否相等。 MSDN
验证两个指定的集合是否相同。如果集合不相等，则断言失败。 MSDN
产生两个序列的集合差异。 MSDN