Get Row Index in a list by using entity framework

Question

I have 5 datas in my list.

MyList

So i want to know , how can i get selected Id's Row Number ?

var MyProductId= 135;
var SelectedDataRowNumber = context.SP_MyList.ToList()
                                   .Where(s=>s.Id==MyProductId)
                                   .FirstOrDefault();

As instance, My List has 5 datas like below,

Id-Name

6,Computer

135,KeyBoard

68,Mouse

98,Telephone

213,Laptop,

MyProductId is 135 so it matchs with Keyboard.It is row count number( index )must be "1" because 0 is Computer.

How can i get selected Id's row count(index) number ?

what do you mean by Row number? Can you please add some example data, of what the objects in your list look like? — Marco, Nov 28 '13 at 07:09

score 7 · Accepted Answer · answered Nov 28 '13 at 07:22

You can get it directly the element by Index if your list has implemented indexer. You can find that How to implement Indexer.

Another way could be as described in Here.

The above link shows it like:

COPIED From Above link:

Person agedTwenty = myList.Where<Person>( x => return x.Age == 20; ).Single<Person>();
int index = myList.IndexOf(agedTwenty);

or alternatively

int index = myList.Where<Person>( x => return x.Age == 20; ).Select<Person,int>( x =>         
myList.IndexOf(x)).Single<int>();

In case there can be more than one result you'd do this:

IEnumerable<Person> allAgedTwenty = myList.Where<Person>( x => return x.Age == 20; );
IEnumerable<int> indices = allAgedTwenty.Select<Person,int>( x => myList.IndexOf(x) );

The first case will get you only one int and the second case will leave you with a list of ints.

Marco · Answer 2 · 2013-11-28T07:45:22.707

If you want the count you need to groupBy

var SelectedDataRowNumber = context.SP_MyList.ToList()
                                   .GroupBy(x = x.Id)
                                   .Where(s=>s.Key == MyCustomerId )
                                   .Select(x => new {Id = x.Key, Count = x.Count()});

This gives you the output

Id = 135
Count = 3 //depending on the actual count

alternative solution, if you want to output id, name and count:

//"items" is my custom list I created to reflect your data
var SelectedDataRowNumber = from x in items 
                            group x by new {x.Id, x.Name} into g
                            where g.Key.Id == 135
                            select new 
                            {
                                ID = g.Key.Id, 
                                Name = g.Key.Name, 
                                Count = g.Count()
                            };

Regarding your comment: is this the result you are expecting: http://abload.de/img/so1j5rta.jpg ?

If you take `SelectedDataRowNumber.Count()` it will be always 1 if you grouped by Id and filtered it by Id afterwards. The count you want is in the result set. — Marco, Nov 28 '13 at 07:30

Get Row Index in a list by using entity framework

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