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C# Linq - Select Multiple Fields where one field should also be filtered with a select

I'm a little bit stuck in Linq.
So first - I show you first the entities. I have a List let's name it "PersonalList" with another List of ListMembers.
public class PersonalList
{
public PersonalList();
public List<ListMember> ListMembers { get; set; }
public long ListNumber {get; set; }
public string Description {get; set;}
}
Here is the ListMember Class:
public class ListMember
{
public ListMember();
public string MemberName{ get; set; }
public long ListId {get; set; }
public string MemberType {get; set; }
public string Position {get; set; }
}
So now im my AppClass I have a List of the PersonalLists.
And I want to create a Dictionary, which has the PersonalList.ListNumber as Key and the Value should be the MemberName AND the MemberType.
What I have tried in first step is:
var personalLists = _allPersonalLists.Select(x => new {x.ListNumber, x.ListMembers).ToArray();
This solves the Problem with ListNumbers as Key. Now I want to have the ListMembers to be filtered so I have tried:
var personalLists = _allPersonalLists.Select(x => new {x.ListNumber, x.ListMembers.Select(y => new {y.MemberName, y.MemberType})}).ToArray();
But here - I get a compile error with following error message:
Error CS0746: Invalid anonymous type member declarator. Anonymous type
members must be declared with a member assignment, simple name or
member access.
So how can I achieve my goal? Any suggestions?

I tried to simulate your scenario and following solution will work for you.
public class PersonalList
{
public List<ListMember> ListMembers { get; set; }
public long ListNumber { get; set; }
public string Description { get; set; }
}
public class ListMember
{
public string MemberName { get; set; }
public long ListId { get; set; }
public string MemberType { get; set; }
public string Position { get; set; }
}
static void Main(string[] args)
{
List<PersonalList> _allPersonalLists = new List<PersonalList>();
for (int i = 1; i <= 5; i++)
{
List<ListMember> ListMembers = new List<ListMember>();
for (int j = 1; j <= 3; j++)
ListMembers.Add(new ListMember() { ListId = j, MemberName = "Member" + i + j, MemberType = "Type" + i, Position = "Position" + i });
_allPersonalLists.Add(new PersonalList() { ListNumber = i, ListMembers = ListMembers, Description = "Desc" + i });
}
var personalLists = _allPersonalLists.ToDictionary(x => x.ListNumber, x => x.ListMembers.Select(y => new { y.MemberName, y.MemberType }).ToList());
Console.ReadLine();
}

var personalLists = _allPersonalLists
.Select(x => new
{
x.ListNumber,
members = x.ListMembers
.Select(y => new
{
y.MemberName,
y.MemberType
}).ToList()
}).ToArray();
`.ToList()` i included to keep actual values otherwise it will be enumerable

How to fill mongo Db table by C# Driver?

I am not an expert of nosql but a year ago I created a mongodb table by using below code:
const string connectionString = "mongodb://localhost:27017";
// Create a MongoClient object by using the connection string
var client = new MongoClient(connectionString);
////Use the MongoClient to access the server
var database = client.GetDatabase("YUSUF");
////get mongodb collection
var collection = database.GetCollection("expressions");
var expression = new Expression { Id = Guid.NewGuid().ToString(),ExpressionSentence = "Test",Name = "yusuf",CreatedDate = DateTime.Now,Status = true };
collection.InsertOneAsync(expression);
public class Expression {
[BsonId]
public string Id { get; set; }
public string Name { get; set; }
public string ExpressionSentence { get; set; }
public bool Status { get; set; }
public DateTime CreatedDate { get; set; }
}
Today above codes is doing nothing now. Not working also not throwing any error. What am I doing wrong?

static void insert()
{
var connectionString = "mongodb://localhost:27017";
var client = new MongoClient(connectionString);
var database = client.GetDatabase("YUSUF");
var collection = database.GetCollection<Expression>("expressions");
var expression = new Expression { Id = Guid.NewGuid().ToString(),ExpressionSentence = "Test",Name = "yusuf",CreatedDate = DateTime.Now,Status = true };
collection.InsertOneAsync(expression);
}
public class Expression {
[BsonId]
public string Id { get; set; }
public string Name { get; set; }
public string ExpressionSentence { get; set; }
public bool Status { get; set; }
public DateTime CreatedDate { get; set; }
}
have to work with the latest C# MongoDB Driver.
MY METHOD
static void insert()
{
var connectionString = "mongodb://localhost:27017";
var client = new MongoClient(connectionString);
var database = client.GetDatabase("fairytale");
// var unicorns = database.GetCollection("unicorns");
var unicorns = database.GetCollection<BsonDocument>("unicorns");
int i = 0;
while (i < 5000)
{
var document = new BsonDocument
{
{"name",GenerateRandomUnicornName()},
{"horns",Random.Next(50)},
{"likes",new BsonArray{ "apple", "onion" }},
};
unicorns.InsertOneAsync(document);
i++;
}
}

Converting Dataset to IList [duplicate]

This question already has answers here:
Convert DataSet to List
(11 answers)
Closed 8 years ago.
I am using SqlHelper to execute the stored procedure in the DB.
In a namespace called constants i defined something like this
public class ShowInstitutes
{
public string InstituteName { get; set; }
public string InstituteCity { get; set; }
public int InstituteId { get; set; }
}
In the DAL layer I am trying to execute stored proc and get results in IList format
public IList<ShowInstitutes> ShowInstitutes(int instituteId)
{
return SqlHelper.ExecuteDataset(dBConnection, "usp_SPName");
}
I am getting the following error:
Cannot implicitly convert type 'System.Data.DataSet' to 'System.Collections.Generic.IList<>

You can converting your Dataset result to IList like this.
public IList<ShowInstitutes> ShowInstitutes(int instituteId)
{
var dataTable = SqlHelper.ExecuteDataset(dBConnection, "usp_SPName");
var SourceLists = new List<ShowInstitutes>();
for (var index = 0; index < dataTable.Rows.Count; index++)
{
SourceLists.Add(new ShowInstitutes
{
InstituteName = Convert.ToString(dataTable.Rows[index]["Columnname"], CultureInfo.InvariantCulture),
InstituteCity = Convert.ToString(dataTable.Rows[index]["Columnname"], CultureInfo.InvariantCulture),
InstituteId = Convert.ToInt32(dataTable.Rows[index]["Columnname"], CultureInfo.InvariantCulture)
});
}
return SourceLists;
}

public IList<ShowInstitutes> ShowInstitutes(int instituteId)
{
var d = SqlHelper.ExecuteDataset(dBConnection, "usp_SPName");
var myData = d.Tables[0].AsEnumerable().Select(data => new ShowInstitutes{
InstituteName = data.Field<string>("InstituteName "),
InstituteCity = data.Field<string >("InstituteCity "),
InstituteId = data.Field<int>("InstituteId ")
});
var list = myData.ToList();
return list;
}

public class info
{
public string counter
{
get; set;
}
public string age
{
get;
set;
}
public string id
{
get;
set;
}
public string marks
{
get;
set;
}
public string name
{
get;
set;
}
public List<info> getdata()
{
string c = "Data Source=bla ;bla ;bla";
SqlConnection con = new SqlConnection(c);
DataSet ds = SqlHelper.ExecuteDataset(con, CommandType.Text, "SELECT * from table1");
var list = (ds.Tables[0].AsEnumerable().Select(
df =>
new info
{
age = df[0].ToString(),
counter = df[1].ToString(),
id = df[3].ToString(),
name = df[4].ToString(),
marks = df[2].ToString()
})).ToList();
return list;
}
}
class Program
{
static void Main(string[] args)
{
info a =new info();
List<info> list1= a.getdata();
foreach (var info in list1)
{
Console.WriteLine(info.name+" "+info.age+" "+info.marks);
}
Console.Read();
}
}

Entity Framework - Conditionally include related entities

I maintain an API that, based on a request for a list of people, returns a different result set based on the request. For example, some API clients want to get a list of people and a list of their interactions, others want people and a list of their metadata. All this can be specified int he request to the API method that returns people.
This does not appear to work:
using (var dbcontext = new ExampleEntities())
{
var query = dbcontext.People.AsQueryable();
//determined in earlier application logic based on request
if(includeMetadata)
{
query = query.Include("metadata");
}
//determined in earlier application logic based on request
if(includeInteractions)
{
query = query.Include("interactions");
}
/* ...SNIP... */
}
What I don't want to do is this:
var query = dbcontext.People.Include("Metadata").Include("interactions");
which will mean every request to get a person will include ALL their related entities, even if the requesting API client does not need them.
I also don't want to code every possible combination of logic:
if(includeMetadata && includeInteractions)
{
var query = dbcontext.People.Include("Metadata").Include("interactions");
}
else if(includeMetadata)
{
var query = dbcontext.People.Include("Metadata");
}
else if(includeInteractions)
{
var query = dbcontext.People.Include("Interactions");
}
else
{
var query = dbcontext.People;
}
This will result in hard-to-maintain code, however, I realize I could code generate this if needed.

You can chain the IQueryable's
using (var dbcontext = new ExampleEntities())
{
var query = dbcontext.People.AsQueryable();
if(includeMetadata)
{
query = query.Include("metadata");
}
if(includeInteractions)
{
query = query.Include("interactions");
}
}

Your first example should work if you replace u with query
u = u.Include("metadata");
with
query = query.Include("metadata");

Works fine here... checking the sql statements with the EF 6 Log handler
[TestClass]
public void SomeTestClass
{
[TestMethod]
public void ShouldLoadOnlyRequiredCollections()
{
Database.SetInitializer(new DropCreateDatabaseAlways<HomesContext>());
var db = new HomesContext();
Assert.IsFalse(db.Homes.Any());
var home = db.Homes.Create();
db.Homes.Add(home);
home.Staff.Add(new Staff { Name = "wilma" });
home.Staff.Add(new Staff { Name = "betty" });
home.Residents.Add(new Resident { Name = "fred" });
home.Residents.Add(new Resident { Name = "barney" });
db.SaveChanges();
db = null;
Database.SetInitializer(new DropCreateDatabaseIfModelChanges<HomesContext>());
var sb = new StringBuilder();
db = new HomesContext();
db.Database.Log = ((s) => { sb.Append(s + "\r"); });
Assert.IsTrue(db.Homes.Any());
string log;
log = sb.ToString();
Assert.IsTrue(sb.ToString().Contains("FROM [dbo].[Homes]"));
sb = new StringBuilder(); //ok get residents
var q = db.Homes.Include("Residents");
Assert.IsTrue(string.IsNullOrEmpty(sb.ToString()));
var lst = q.ToList();
log = sb.ToString();
Assert.IsTrue(sb.ToString().Contains("[dbo].[Homes]"));
Assert.IsTrue(sb.ToString().Contains("[dbo].[Residents]"));
Assert.IsTrue(!sb.ToString().Contains("[dbo].[Staff]"));
sb = new StringBuilder(); //get staff
q = db.Homes.Include("Staff");
Assert.IsTrue(string.IsNullOrEmpty(sb.ToString()));
lst = q.ToList();
log = sb.ToString();
Assert.IsTrue(log.Contains("[dbo].[Homes]"));
Assert.IsTrue(!log.Contains("[dbo].[Residents]"));
Assert.IsTrue(log.Contains("[dbo].[Staffs"));
sb = new StringBuilder(); //get residents and staff
q = db.Homes.Include("Staff");
q = q.Include("Residents");
lst = q.ToList();
log = sb.ToString();
Assert.IsTrue(log.Contains("[dbo].[Homes]"));
Assert.IsTrue(log.Contains("[dbo].[Residents]"));
Assert.IsTrue(log.Contains("[dbo].[Staffs]"));
}
}
public class HomesContext:DbContext
{
public DbSet<Home> Homes { get; set; }
}
public class Home
{
public Home()
{
Staff = new List<Staff>();
Residents = new List<Resident>();
}
public int HomeId { get; set; }
public string HomeName { get; set; }
public int MaxResidents { get; set; }
public int MaxStaff { get; set; }
public int CurrentResidents { get; set; }
[NotMapped]
public int CurrentStaff { get; set; }
public IList<Staff> Staff { get; set; }
public IList<Resident> Residents { get; set; }
}
public class Staff
{
public int StaffId { get; set; }
public string Name { get; set; }
public int HomeId { get; set; }
public Home Home { get; set; }
}
public class Resident
{
public int ResidentId { get; set; }
public string Name { get; set; }
public int HomeId { get; set; }
public Home Home { get; set; }
}

select child object collection with lambdas

I have the following class objects:
public class VacancyCategory
{
public int ID { get; set; }
public string Text { get; set; }
public IList<VacancySubCategory> SubCategories { get; set; }
}
public class VacancySubCategory
{
public int ID { get; set; }
public string Text { get; set; }
public VacancyCategory Category { get; set; }
public IList<Vacancy> Vacancies { get; set; }
}
public class Vacancy : IBusinessObject
{
public int ID { get; set; }
public string Title { get; set; }
public VacancySubCategory SubCategory { get; set; }
public string Body { get; set; }
public VacancyWorkType WorkType { get; set; }
public string Salary { get; set; }
public DateTime? AppsClosingDate { get; set; }
public bool Active { get; set; }
}
...so in a test repository im creating test data like so:
private IList<VacancyCategory> GetVacancyCategoriesWithAllChildCollections()
{
IList<VacancyCategory> vacancyCategories = new List<VacancyCategory>();
int cCounter = 0;
int scCounter = 0;
int vCounter = 0;
for (int i = 1; i <= 3; i++)
{
VacancyCategory vc = new VacancyCategory();
vc.ID = ++cCounter;
vc.Text = "VacancyCategory" + i.ToString();
for (int j = 1; j <= 3; j++)
{
VacancySubCategory vsc = new VacancySubCategory();
vsc.ID = ++scCounter;
vsc.Text = "VacancySubCategory" + scCounter.ToString();
vsc.Category = vc;
for (int k = 1; k <= 2; k++)
{
Vacancy v = new Vacancy();
v.ID = ++vCounter;
v.Title = "Vacancy" + vCounter.ToString();
v.Body = "VacancyBody" + vCounter.ToString();
v.Active = vCounter >= 16 ? false : true;
v.WorkType = this._workTypes.Single(wt => wt.ID == k);
v.Salary = vCounter <= 7 ? "SR " + (vCounter * 1000).ToString() : "";
v.AppsClosingDate = (vCounter >= 3 & vCounter <= 13) ? (new DateTime(2009, 3, vCounter)) : (DateTime?)null;
v.SubCategory = vsc;
if (vsc.Vacancies == null)
vsc.Vacancies = new List<Vacancy>();
vsc.Vacancies.Add(v);
}
if (vc.SubCategories == null)
vc.SubCategories = new List<VacancySubCategory>();
vc.SubCategories.Add(vsc);
}
vacancyCategories.Add(vc);
}
return vacancyCategories;
}
..so now i have some good test data. the object tree / chained objects are important to me.
so i'd like to return the individual object collections from this tree when desired. for example, if i wanted the whole tree, i can just return the VacancyCategory list with all the child objects - great. but now i want to return just the VacancySubCaregory items (all 9 of them). this would be my public method to the test repository:
public IQueryable<VacancySubCategory> GetVacancySubCategories()
{
throw new NotImplementedException("write gen code");
}
.. obviously without the exception. i have a member field called _categories that contains the results from the GetVacancyCategoriesWithAllChildCollections method. so i've been trying stuff like
this._categories.Select( ......
..but i cant seem to return a list of VacancySubCategory objects. i seem to always be selecting the root collection (ie. a result set of VacancyCategory objects). What am i doing wrong? im sure its simple... but its driving me nuts!
EDIT
thanx matt.
your suggestion led me to this:
public IQueryable<VacancySubCategory> GetVacancySubCategories()
{
return this._categories.SelectMany(c => c.SubCategories).AsQueryable<VacancySubCategory>();
}
..which works great. you're a champ

Try:
return this._categories.SelectMany(c => c.SubCategories);

This should work.
var query = from vc in GetVacancyCategoriesWithAllChildCollections()
from vcs in vc.SubCategories
select vcs