Sorting a list of a custom class

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I am writing a web application. I have written a class

class person{<br />
  string FirstName = "";<br />
  int rank = 0;<br />
  int LastName = "";<br />
}

I have a list of "people" and want to sort them by rank - IE. highest rank first

for example.

Say I have someone called bob at a rank of 2 and someone called rob with a rank of 4 and someone called wob with a rank of 1

(I'm great with coming up with names)

I want to sort this list so the outcome would be this:

rob - 4<br />
bob - 2<br />
wob - 1

Can anyone help?

Posted 26-Aug-12 18:13pm

Kodemaster123

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3 solutions

Solution 1

Where are you stuck? To get you started, you can use the IComparable<T> interface to create custom sorting of lists. Refer to the following link:

http://msdn.microsoft.com/en-us/library/4d7sx9hd.aspx[^]

http://addinit.com/node/50[^]

Hope this helps!

Posted 26-Aug-12 18:22pm

Karthik. A

Solution 3

C#

List<person> ToBeSortedList ;//modify to appropriate list name

List<person> SortedbyRankPersonList = (ToBeSortedList.OrderByDescending(c => c.rank)).ToList();

Thanks,

Kuthuparakkal

Posted 26-Aug-12 19:28pm

Kuthuparakkal

Updated 26-Aug-12 19:29pm

v2

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pramod.hegde · Accepted Answer · 2012-08-26T20:01:00

Solution 4

C#

public class Person{
	public string FirstName {get;set;}
	public int Rank {get;set;}
	public string LastName {get;set;}
}

List<person> personList = new List<person>();
personList.Add(new Person(){ FirstName="bob", Rank=2 });
personList.Add(new Person(){ FirstName="wob", Rank=1 });
personList.Add(new Person(){ FirstName="rob", Rank=4 });

var result =  from v in (from p in personList
                         select p).OrderByDescending(x=>x.Rank)
              select new
                  {
		ResultValue = String.Format("{0} - {1}",v.FirstName,v.Rank)
	      };

This would result

rob - 4
bob - 2
wob - 1

Posted 26-Aug-12 20:01pm

pramod.hegde

Updated 26-Aug-12 20:22pm

v2

Comments

Kodemaster123 27-Aug-12 4:38am

I forgot to mention that I can't use system.linq - is there any way to do this without using this lib?

pramod.hegde 27-Aug-12 5:07am

Then you might need to write the logic by your own.
Something like this,

Person[] personList = new Person[4]; // fill this

int n=personList.Length;
Person temp = null;

for (int i = 0; i < n-1; i++)
{
for (int j = i + 1; j < n; j++)
{
if (personList[i].Rank < personList[i].Rank)
{
temp = personList[i];
personList[i] = personList[j];
personList[j] = temp;
}
}
}

This will sort according to the Rank.

Kodemaster123 27-Aug-12 22:29pm

Thanks! This solved my problem!

I noticed one error in your coding though:
if (personList[i].Rank < personList[i].Rank)
should have been
if (personList[i].Rank < personList[j].Rank)

Nobody's perfect

Thanks!!!!
Kodemaster123