Get next item in list c# and update the current one

Question

I have a list like this

List<NamazTimesModel> res = nt.Select();

In res I have data like this

[
{
"name": "fajr",
"salahTime": "05:23",
"namazTime": "05:23",
"date": "3/6/2017 12:00:00 AM",
"endTime": null
},
{
"name": "sunrise",
"salahTime": "07:01",
"namazTime": "07:01",
"date": "3/6/2017 12:00:00 AM",
"endTime": null
},
{
"name": "zuhr",
"salahTime": "12:33",
"namazTime": "12:33",
"date": "3/6/2017 12:00:00 AM",
"endTime": null
},
....
]

I am looping over the list and checking what is the current item. For example it is 'fajr' then I have to take the next item and get the 'salahTime' from there and set 'endTime' of fajr to be that.

Can I get some help?

Possible duplicate of [LINQ Next Item in List](http://stackoverflow.com/questions/2680228/linq-next-item-in-list) — NineBerry, Mar 06 '17 at 13:00
care to include how exactly you are looping through the list? — Mong Zhu, Mar 06 '17 at 13:01
@NineBerry I think OP wants slightly more than his title says: he needs the current item, in addition to the next one, so that he could modify its properties. — Sergey Kalinichenko, Mar 06 '17 at 13:05

score 1 · Answer 1 · answered Mar 06 '17 at 13:01

You can skip list items while your target item is not found, then grab the target item itself, along with the next one:

var twoItems = res.SkipWhile(item => item.Name != "fajr").Take(2).ToList();

If you have exactly two items in twoItems list, then you found fajr, and it wasn't the last item on the list. If you have fewer than two items, then either fajr wasn't there, or it was the last item on the list.

Check that you have two items, and set fields as necessary:

if (twoItems.Count == 2) {
    twoItems[0].EndTime = twoItems[1].SalahTime;
}

score 1 · Accepted Answer · answered Mar 06 '17 at 13:03

Something like this should do it:

   var res = nt.Aggregate(new List<NamazTimesModel>(), (t, i) =>
            {
                if (t.Count > 0)
                {
                    t[t.Count - 1].endTime = i.salahTime;
                }
                t.Add(i);
                return t;
            }
        );

score 0 · Answer 3 · edited Mar 06 '17 at 13:56

0

for(int i = 1; i < res.Count; i++)
{
   // Todo: Check for null references by your own way.
   res[i - 1].endTime = res[i].salahTime;
}

edited Mar 06 '17 at 13:56

Hakan Fıstık

16,800
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answered Mar 06 '17 at 13:06

ravindra

322
3
14

score 0 · Answer 4 · answered Mar 06 '17 at 13:09

0

You can set Namaz times as below,

for(var i = 0; i<nts.Count()-1; i++){
 nt[i].EndTime = nt[i+1].SalahTime
}

Then don't forget to set last Namaz time:

nts[nt.Count()-1] = nts[0].SalahTime;

answered Mar 06 '17 at 13:09

asdf_enel_hak

7,474
5
42
84

score 0 · Answer 5 · edited Mar 06 '17 at 13:57

0

res.ForEach(item =>
{
     int index = res.FindIndex(m => m.name == item.name);
     item.endTime = index+1 != res.Count ? res.ElementAt(index + 1).salahTime : res.FirstOrDefault().salahTime;
});;

edited Mar 06 '17 at 13:57

Hakan Fıstık

16,800
14
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131

answered Mar 06 '17 at 13:34

NikhilGoud

574
1
5
21

score 0 · Answer 6 · answered Mar 06 '17 at 14:22

You can do two iterations with linq query.

It will be like this:

string[] numbers= {"one","two","last"}; string[] variables={"string one","int two","string three"}; var res = variables.Where(v => numbers.Any(n => v.Contains(n ))); res.ToList().ForEach(d => Console.WriteLine(d));

working code here.

Get next item in list c# and update the current one

6 Answers6