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IF statement inside a LINQ SELECT to include columns

Is it possible to include or exclude column within linq Select?
var numberOfYears = Common.Tool.NumberOfYear;
var list = users.Select(item => new
{
Id = item.Id,
Name= item.Name,
City= Item.Address.City.Name,
STATUS = Item.Status,
if(numberOfYears == 1)
{
Y1 = item.Records.Y1,
}
if(numberOfYears == 2)
{
Y1 = item.Records.Y1,
Y2 = item.Records.Y2,
}
if(numberOfYears == 3)
{
Y1 = item.Records.Y1,
Y2 = item.Records.Y2,
Y3 = item.Records.Y3,
}
}).ToList();
}
The idea is that i want to display Y1,Y2,Y3 only if has values

Thanks to the beauty of the dynamic keyword what you need is now possible in C#. Below an example:
public class MyItem
{
public string Name { get; set; }
public int Id { get; set; }
}
static void Main(string[] args)
{
List<MyItem> items = new List<MyItem>
{
new MyItem
{
Name ="A",
Id = 1,
},
new MyItem
{
Name = "B",
Id = 2,
}
};
var dynamicItems = items.Select(x => {
dynamic myValue;
if (x.Id % 2 == 0)
myValue = new { Name = x.Name };
else
myValue = new { Name = x.Name, Id = x.Id };
return myValue;
}).ToList();
}
This will return a list of dynamic objects. One with 1 property and one with 2 properties.

Try this approach:
var numberOfYears = Common.Tool.NumberOfYear;
var list = users.Select(item => new
{
Id = item.Id,
Name = item.Name,
City = Item.Address.City.Name,
STATUS = Item.Status,
Y1 = numberOfYears > 0 ? item.Records.Y1 : 0,
Y2 = numberOfYears > 1 ? item.Records.Y2 : 0,
Y3 = numberOfYears > 2 ? item.Records.Y3 : 0
}).ToList();
Instead of 0, add your default value or null.
Update:
According to your comments, the only option for you is to go dynamic. Here's example with dynamics:
var numberOfYears = 3;
var list = users.Select(x =>
{
dynamic item = new ExpandoObject();
item.Id = x.Id;
item.Name = x.Name;
item.Status = x.Status;
var p = item as IDictionary<string, object>;
var recordsType = x.Records.GetType();
for (var i = 1; i <= numberOfYears; ++i)
p["Y" + i] = recordsType.GetProperty("Y" + i).GetValue(x.Records);
return item;
}).ToList();

You can use the ExpandoObject like this:
var data = providers.Select(provider =>
{
dynamic excelRow = new ExpandoObject();
excelRow.FirstName = provider.FirstName ?? "";
excelRow.MiddleName = provider.MiddleName ?? "";
excelRow.LastName = provider.LastName ?? "";
// Conditionally add columns to the object...
if (someCondition)
{
excelRow.Property1ForCondition = provider.Property1ForCondition;
excelRow.Property2ForCondition = provider.Property2ForCondition;
}
excelRow.DueDate = provider.DueDate ?? null;
.
.
.
return excelRow;
});
Another variation of the above code can be:
var data = new List<ExpandoObject>();
providers.ForEach(provider =>
{
dynamic excelRow = new ExpandoObject();
excelRow.FirstName = provider.FirstName ?? "";
excelRow.MiddleName = provider.MiddleName ?? "";
excelRow.LastName = provider.LastName ?? "";
// Conditionally add columns to the object...
if (someCondition)
{
excelRow.Property1ForCondition = provider.Property1ForCondition;
excelRow.Property2ForCondition = provider.Property2ForCondition;
}
excelRow.DueDate = provider.DueDate ?? null;
.
.
.
data.Add(excelRow);
});

How to return Distinct Row using LINQ

I have two rows which have all the data same except one column.
I want to show only one row on the UI but one row which has different data should be shown as comma seperated values.
Sample Data
PricingID Name Age Group
1 abc 56 P1
1 abc 56 P2
Output should be :
PricingID Name Age Group
1 abc 56 P1,P2
I am using this approach but it is not working , it gives me two rows only but data i am able to concatenate with comma.
List<PricingDetailExtended> pricingDetailExtendeds = _storedProcedures.GetPricingAssignment(pricingScenarioName, regionCode, productCode, stateCode, UserId, PricingId).ToList();
var pricngtemp = pricingDetailExtendeds.Select(e => new
{
PricingID = e.PricingID,
OpportunityID = e.OpportunityID,
ProductName = e.ProductName,
ProductCD = e.ProductCD
});
pricingDetailExtendeds.ForEach(e=>
{
e.ProductCD = string.Join(",",string.Join(",", (pricngtemp.ToList().Where(p => p.PricingID == e.PricingID).Select(k => k.ProductCD).ToArray())).Split(',').Distinct().ToArray());
e.OpportunityID =string.Join(",", string.Join(",", (pricngtemp.ToList().Where(p => p.PricingID == e.PricingID).Select(k => k.OpportunityID).ToArray())).Split(',').Distinct().ToArray());
e.ProductName =string.Join(",", string.Join(",", (pricngtemp.ToList().Where(p => p.PricingID == e.PricingID).Select(k => k.ProductName).ToArray())).Split(',').Distinct().ToArray());
}
);
// pricingDetailExtendeds = GetUniquePricingList(pricingDetailExtendeds);
return pricingDetailExtendeds.Distinct().AsEnumerable();
Any body can suggest me better approach and how to fix this issue ?
Any help is appreciated.

You want to use the GroupBy linq function.
I then use the String.Join function to make the groups comma seperated.
So something like this:
var pricingDetailExtendeds = new[]
{
new
{
PricingID = 1,
Name = "abc",
Age = 56,
Group = "P1"
},
new
{
PricingID = 1,
Name = "abc",
Age = 56,
Group = "P2"
}
};
var pricngtemp =
pricingDetailExtendeds.GroupBy(pde => new {pde.PricingID, pde.Name, pde.Age})
.Select(g => new {g.Key, TheGroups = String.Join(",", g.Select(s => s.Group))}).ToList();
You can easily extrapolate this to the other fields.
To return the PricingDetailExtended, the just create it in the select. So something like this
.Select(g => new PricingDetailExtended {
PricingID = g.Key.PricingId,
TheGroups = String.Join(",", g.Select(s => s.Group))
}).ToList();
You won't have the field TheGroups though, so just replace that field with the proper one.

An example of what I was describing in my comment would be something along the lines of the following. I would expect this to be moved into a helper function.
List<PriceDetail> list = new List<PriceDetail>
{
new PriceDetail {Id = 1, Age = 56, Name = "abc", group = "P1"},
new PriceDetail {Id = 1, Age = 56, Name = "abc", group = "P2"},
new PriceDetail {Id = 2, Age = 56, Name = "abc", group = "P1"}
};
Dictionary<PriceDetailKey, StringBuilder> group = new Dictionary<PriceDetailKey, StringBuilder>();
for (int i = 0; i < list.Count; ++i)
{
var key = new PriceDetailKey { Id = list[i].Id, Age = list[i].Age, Name = list[i].Name };
if (group.ContainsKey(key))
{
group[key].Append(",");
group[key].Append(list[i].group);
}
else
{
group[key] = new StringBuilder();
group[key].Append(list[i].group);
}
}
List<PriceDetail> retList = new List<PriceDetail>();
foreach (KeyValuePair<PriceDetailKey, StringBuilder> kvp in group)
{
retList.Add(new PriceDetail{Age = kvp.Key.Age, Id = kvp.Key.Id, Name = kvp.Key.Name, group = kvp.Value.ToString()});
}
you could even convert the final loop into a LINQ expression like:
group.Select(kvp => new PriceDetail {Age = kvp.Key.Age, Id = kvp.Key.Id, Name = kvp.Key.Name, group = kvp.Value.ToString()});
Its worth noting you could do something similar without the overhead of constructing new objects if, for example, you wrote a custom equality comparer and used a list instead of dictionary. The upside of that is that when you were finished, it would be your return value without having to do another iteration.
There are several different ways to get the results. You could even do the grouping in SQL.

c# - AutoMapper: how to copy fields from 2 different sources into 1 destination

I have a flat file with a bunch of records, let's say it's a sequence of 2 record types
--- Record1: ID;NAME;SURNAME
--- Record2: AGE;SEX;
Let's call R1 the class representing Record1 and R2 the class representing Record2
In this moment I have an array of R1 and another array of R2
If I have a POCO called Subject that has 5 fields, named exactly as the union of the fields of R1 and R2, how do I configure AutoMapper to do the magic for me?
Now I'm trying this:
var subjects = Mapper.Map<IEnumerable<R1>, List<Subject>>(arrayOfR1s);
Mapper.Map<IEnumerable<R2>, List<Subject>>(arrayOfR2s, subjects);
After the first mapping, I get an array of Subjects, in every element of the array the fields ID, SURNAME, NAME are correctly filled with values. AGE and SEX are left to NULL as expected.
But after the second mapping, all the fields from R1 (ID, NAME, SURNAME) are initialized to NULL and I only get fields from R2 (AGE and SEX).
How do I get the complete union of the fields?
Can someone point me to the right approach?

How about the straightforward dynamic mapping of joined (anonymously typed) objects?
Record1[] firstRecords = new[]
{
new Record1
{
ID = Guid.NewGuid(),
Name = "John", Surname = "Doe"
},
new Record1
{
ID = Guid.NewGuid(),
Name = "Jane", Surname = "Roe"
}
};
Record2[] secondRecords = new[]
{
new Record2 { Age = 20, Sex = Sex.Male },
new Record2 { Age = 20, Sex = Sex.Female }
};
var subjects = firstRecords
.Select((first, index) =>
{
var second = secondRecords[index];
var r = new
{
ID = first.ID,
Name = first.Name,
Surname = first.Surname,
Age = second.Age,
Sex = second.Sex
};
return Mapper.DynamicMap<Subject>(r);
})
.ToArray();
By the way, you can map these object without using AutoMapper, but using LINQ Select().
var subjects = firstRecords
.Select((first, index) =>
{
var second = secondRecords[index];
var r = new Subject
{
ID = first.ID,
Name = first.Name,
Surname = first.Surname,
Age = second.Age,
Sex = second.Sex
};
return r;
})
.ToArray();
Update
If you need to copy a lot of properties, please take a look at the Value Injecter. InjectFrom() FTW!
var subjects = firstRecords
.Select((first, index) =>
{
var second = secondRecords[index];
var r = new Subject();
r.InjectFrom(first).InjectFrom(second);
return r;
})
.ToArray();

Most efficient way of loading data into LINQ object for search result type method

I currently have the following:
public IEnumerable<News> NewsItems
{
get { return from s in News.All() where s.Description.Contains(SearchCriteria) || s.Summary.Contains(SearchCriteria) select s; }
}
The problem is I only need to return the one property that actually has the data as well as the Title property, something similar to.
return from s in News.All() where s.Description.Contains(SearchCriteria) || s.Summary.Contains(SearchCriteria) select new {Title = s.Title, Data = //Description or Summary containing the data
How do I determine which one contains the search query?
UPDATE: I have this but it obviously hits the DB 3 times
var FoundInSummary = News.All().Any(x => x.Summary.Contains(SearchCriteria));
var FoundInDesc = News.All().Any(x => x.Description.Contains(SearchCriteria));
IEnumerable<NewsEventSearchResults> result = null;
if ((FoundInSummary && FoundInDesc) || (FoundInSummary))
{
result = (from s in News.All() where s.Summary.Contains(SearchCriteria) select new NewsEventSearchResults { Title = s.Title, Data = s.Summary, ID = s.ID }).AsEnumerable();
}
else if (FoundInDesc)
{
result = (from s in News.All() where s.Description.Contains(SearchCriteria) select new NewsEventSearchResults { Title = s.Title, Data = s.Description, ID = s.ID }).AsEnumerable();
}
return result;
UPDATE 2: Is this more efficent?
var ss = (from s in News.All() where s.Description.Contains(SearchCriteria) || s.Summary.Contains(SearchCriteria) select s).ToList();
List<NewsEventSearchResults> resultList = new List<NewsEventSearchResults>();
foreach (var item in ss)
{
bool FoundInSummary = item.Summary.Contains(SearchCriteria);
bool FoundInDesc = item.Description.Contains(SearchCriteria);
if ((FoundInSummary && FoundInDesc) || (FoundInSummary))
{
resultList.Add(new NewsEventSearchResults { Title = item.Title, Data = item.Summary, ID = item.ID });
}
else if (FoundInDesc)
{
resultList.Add(new NewsEventSearchResults { Title = item.Title, Data = item.Description, ID = item.ID });
}
}

What if they both contain the criteria? Or are they mutually exclusive? If so
Data = (s.Description != null ? s.Description : s.Summary)

I went with option 3

Can a single LINQ Query Expression be framed in this scenario?

I am facing a scenario where I have to filter a single object based on many objects.
For sake of example, I have a Grocery object which comprises of both Fruit and Vegetable properties. Then I have the individual Fruit and Vegetable objects.
My objective is this:
var groceryList = from grocery in Grocery.ToList()
from fruit in Fruit.ToList()
from veggie in Vegetable.ToList()
where (grocery.fruitId = fruit.fruitId)
where (grocery.vegId = veggie.vegId)
select (grocery);
The problem I am facing is when Fruit and Vegetable objects are empty.
By empty, I mean their list count is 0 and I want to apply the filter only if the filter list is populated.
I am also NOT able to use something like since objects are null:
var groceryList = from grocery in Grocery.ToList()
from fruit in Fruit.ToList()
from veggie in Vegetable.ToList()
where (grocery.fruitId = fruit.fruitId || fruit.fruitId == String.Empty)
where (grocery.vegId = veggie.vegId || veggie.vegId == String.Empty)
select (grocery);
So, I intend to check for Fruit and Vegetable list count...and filter them as separate expressions on successively filtered Grocery objects.
But is there a way to still get the list in case of null objects in a single query expression?

I think the LINQ GroupJoin operator will help you here. It's similar to the TSQL LEFT OUTER JOIN

IEnumerable<Grocery> query = Grocery
if (Fruit != null)
{
query = query.Where(grocery =>
Fruit.Any(fruit => fruit.FruitId == grocery.FruitId));
}
if (Vegetable != null)
{
query = query.Where(grocery =>
Vegetable.Any(veggie => veggie.VegetableId == grocery.VegetableId));
}
List<Grocery> results = query.ToList();

Try something like the following:
var joined = grocery.Join(fruit, g => g.fruitId,
f => f.fruitId,
(g, f) => new Grocery() { /*set grocery properties*/ }).
Join(veggie, g => g.vegId,
v => v.vegId,
(g, v) => new Grocery() { /*set grocery properties*/ });
Where I have said set grocery properties you can set the properties of the grocery object from the g, f, v variables of the selector. Of interest will obviouly be setting g.fruitId = f.fruitId and g.vegeId = v.vegeId.

var groceryList =
from grocery in Grocery.ToList()
join fruit in Fruit.ToList()
on grocery.fruidId equals fruit.fruitId
into groceryFruits
join veggie in Vegetable.ToList()
on grocery.vegId equals veggie.vegId
into groceryVeggies
where ... // filter as needed
select new
{
Grocery = grocery,
GroceryFruits = groceryFruits,
GroceryVeggies = groceryVeggies
};

You have to use leftouter join (like TSQL) for this. below the query for the trick
private void test()
{
var grocery = new List<groceryy>() { new groceryy { fruitId = 1, vegid = 1, name = "s" }, new groceryy { fruitId = 2, vegid = 2, name = "a" }, new groceryy { fruitId = 3, vegid = 3, name = "h" } };
var fruit = new List<fruitt>() { new fruitt { fruitId = 1, fname = "s" }, new fruitt { fruitId = 2, fname = "a" } };
var veggie = new List<veggiee>() { new veggiee { vegid = 1, vname = "s" }, new veggiee { vegid = 2, vname = "a" } };
//var fruit= new List<fruitt>();
//var veggie = new List<veggiee>();
var result = from g in grocery
join f in fruit on g.fruitId equals f.fruitId into tempFruit
join v in veggie on g.vegid equals v.vegid into tempVegg
from joinedFruit in tempFruit.DefaultIfEmpty()
from joinedVegg in tempVegg.DefaultIfEmpty()
select new { g.fruitId, g.vegid, fname = ((joinedFruit == null) ? string.Empty : joinedFruit.fname), vname = ((joinedVegg == null) ? string.Empty : joinedVegg.vname) };
foreach (var outt in result)
Console.WriteLine(outt.fruitId + " " + outt.vegid + " " + outt.fname + " " + outt.vname);
}
public class groceryy
{
public int fruitId;
public int vegid;
public string name;
}
public class fruitt
{
public int fruitId;
public string fname;
}
public class veggiee
{
public int vegid;
public string vname;
}
EDIT:
this is the sample result
1 1 s s
2 2 a a
3 3