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Delete duplicate elements from list by Identifier string (C#)

I have method to add elements to list
Here is code
public static List<InputDevice> GetAudioInputDevices()
{
var inputs = new List<InputDevice>();
var enumerator = new MMDeviceEnumerator();
var devicesAudio = enumerator.EnumerateAudioEndPoints(DataFlow.Capture, DeviceState.All);
foreach (var device in devicesAudio)
{
inputs.Add(new InputDevice()
{
Name = device.FriendlyName,
Status = device.State.ToString(),
DeviceId = device.ID,
Identifier = device.FriendlyName.Replace(" ", "").ToUpper()
});
}
return inputs;
}
But sometimes I can have duplicates in Identifier
How I can return list without duplicates on return?

There's a few ways to accomplish this, you could just skip the Adding of the item if it's already in the list:
foreach (var device in devicesAudio)
{
string identifier = device.FriendlyName.Replace(" ", "").ToUpper();
if (inputs.Any(input => input.Identifier == identifier))
continue;
inputs.Add(new InputDevice()
{
Name = device.FriendlyName,
Status = device.State.ToString(),
DeviceId = device.ID,
Identifier = identifier
});
}
Or you could group the list by the identifier after the foreach, something like this:
inputs = inputs.GroupBy(i => i.Identifier)
.Select(i => new InputDevice()
{
Identifier = i.Key,
Status = i.First().Status,
DeviceId = i.First().DeviceId,
Name = i.First().Name
}).ToList();
It really depends on what you need to do with the duplicated ones.
Hope it helps!

To make it faster you can use HashSet (complexity of Contains for HashSet is o(1)) and ask on each loop whether there already is a specific identifier in inputs List.
public static List<InputDevice> GetAudioInputDevices()
{
var inputs = new List<InputDevice>();
var enumerator = new MMDeviceEnumerator();
var devicesAudio = enumerator.EnumerateAudioEndPoints(DataFlow.Capture, DeviceState.All);
var usedIdentifiers = new HashSet<string>();
foreach (var device in devicesAudio)
{
var identifier = device.FriendlyName.Replace(" ", "").ToUpper();
if (usedIdentifiers.Contains(identifier))
continue;
inputs.Add(new InputDevice()
{
Name = device.FriendlyName,
Status = device.State.ToString(),
DeviceId = device.ID,
Identifier = identifier
});
usedIdentifiers.Add(identifier);
}
return inputs;
}

The best way, I thing is this
public static List<InputDevice> GetAudioInputDevices()
{
var inputs = new List<InputDevice>();
var enumerator = new MMDeviceEnumerator();
var devicesAudio = enumerator.EnumerateAudioEndPoints(DataFlow.Capture, DeviceState.All);
inputs = devicesAudio.GroupBy(d => d.FriendlyName.Replace(" ", "").ToUpper()).Select(g => g.First())
.Select(d => new InputDevice()
{
Name = d.FriendlyName,
Status = d.State.ToString(),
DeviceId = d.ID,
Identifier = d.FriendlyName.Replace(" ", "").ToUpper()
}).ToList();
return inputs;
}

Check in website information about HashSet.

C# List Join List And Filter From Another List

Need some help constructing proper LINQ query with join.
I have the following setup:
public class Student
{
public string StudentName { get; set; }
public string StudentEmail { get; set; }
}
public class Enrolled
{
public Student Student { get; set; }
public string Subject { get; set; }
}
public class Dropped
{
public Student Student { get; set; }
public string Subject { get; set; }
}
// Populating the List.
// Setup the Student List
List<Student> lstStudents = new List<Student>();
var John = new Student()
{
StudentEmail = "john#stanford.edu",
StudentName = "John Wayne"
};
var Maya = new Student()
{
StudentEmail = "maya#stanford.edu",
StudentName = "Maya Agnes"
};
var Eric = new Student()
{
StudentEmail = "eric#stanford.edu",
StudentName = "Eric James"
};
var Ellen = new Student()
{
StudentEmail = "ellen#stanford.edu",
StudentName = "Ellen Page"
};
lstStudents.Add(John);
lstStudents.Add(Maya);
lstStudents.Add(Eric);
lstStudents.Add(Ellen);
// Setup the Enrolled List
List<Enrolled> lstEnrolled = new List<Enrolled>();
// John
var JohnMath = new Enrolled() { Student = John, Subject = "Math" };
var JohnScience = new Enrolled() { Student = John, Subject = "Science" };
var JohnEnglish = new Enrolled() { Student = John, Subject = "English" };
// Maya
var MayaMath = new Enrolled() { Student = Maya, Subject = "Math" };
// Eric
var EricMath = new Enrolled() { Student = Eric, Subject = "Math" };
var EricScience = new Enrolled() { Student = Eric, Subject = "Science" };
var EricSocial = new Enrolled() { Student = Eric, Subject = "Social" };
// Ellen
var EllenMath = new Enrolled() { Student = Ellen, Subject = "Math" };
var EllenScience = new Enrolled() { Student = Ellen, Subject = "Science" };
var EllenEnglish = new Enrolled() { Student = Ellen, Subject = "English" };
var EllenSocial = new Enrolled() { Student = Ellen, Subject = "Social" };
lstEnrolled.Add(JohnMath);
lstEnrolled.Add(JohnScience);
lstEnrolled.Add(JohnEnglish);
lstEnrolled.Add(MayaMath);
lstEnrolled.Add(EricMath);
lstEnrolled.Add(EricScience);
lstEnrolled.Add(EricSocial);
lstEnrolled.Add(EllenMath);
lstEnrolled.Add(EllenScience);
lstEnrolled.Add(EllenEnglish);
lstEnrolled.Add(EllenSocial);
// Setup the Dropped List
List<Dropped> lstDropped = new List<Dropped>();
// John dropped Math
var JohnDropMath = new Dropped() { Student = John, Subject = "Math" };
// Eric dropped Social
var EricDropSocial = new Dropped() { Student = Eric, Subject = "Social" };
// Ellen Dropped Math
var EllenDropMath = new Dropped() { Student = Ellen, Subject = "Math" };
lstDropped.Add(JohnDropMath);
lstDropped.Add(EricDropSocial);
lstDropped.Add(EllenDropMath);
What I am trying to achieve is get a list of all students, and the subjects they are enrolled in one line, like:
Student Subjects
------- ----------------------------------
John English, Science
Maya Math
Eric Math, Science
Ellen English, Science, Social
I have constructed the following so far:
var StudentsAndCurrentSubjects = (from st in lstStudents
join en in lstEnrolled
on st.StudentName equals en.Student.StudentName
select new
{
st.StudentName,
en.Subject
})
.ToList();
But it is giving me the result per person per subject.
I hit a wall on how to exclude the dropped items from the list.
I am thinking of traversing the dropped list, like:
foreach(d in lstDropped)
{
// Logic to Remove it from the StudentsAndCurrentSubjects
}
But I feel that it is inefficient (especially if I have lots of rows).
I also do not know how to join the subjects in one line.
Looking for some help here.
Thanks.

We just need to first remove dropped subjects from enrolled list. then group by student.
note that we have list for each student, that it has Student and Subject as its fields, we just select the name of first student from each (as they all the same) and join the subjects together.
var result = lstEnrolled.Where(e => !lstDropped.Any(d => d.Student == e.Student && d.Subject == e.Subject)) //omit dropped courses
.GroupBy(x => x.Student) // group results by students
.Select(x => new {
Name = x.First().Student.StudentName.Split(' ').First(),
Subjects = string.Join(", ", x.Select(e => e.Subject))
}).ToArray();
for printing:
foreach(var x in result)
Console.WriteLine($"{x.Name}\t{x.Subjects}");
LIVE DEMO

You are almost there. The join is correct, you just need to actually apply the grouping you want:
var StudentsAndCurrentSubjects = (from st in lstStudents
join en in lstEnrolled
on st.StudentName equals en.Student.StudentName
select new
{
st.StudentName,
en.Subject
})
.GroupBy(s => s.StudentName, d => d.Subject)
.Select(grp => new { StudentName = grp.Key, Subjects = grp.ToList() })
.ToList();
Then you can use the projection above to display it however you want. Something like this maybe:
foreach (var grouping in StudentsAndCurrentSubjects) {
var studentName = grouping.StudentName;
var subjects = string.Join(", ", grouping.Subjects);
Console.WriteLine($"{studentName}\t{subjects}");
}

Try a GroupJoin by using the into keyword.
var studentsAndCurrentSubjects = (
from student in lstStudents
join enrollment in lstEnrolled
on student equals enrollment.Student
into enrollments
join drop in lstDrop
on student equals drop.Student
into drops
let classes = enrollments.Select(e => e.Subject).Except(drops.Select(d => d.Subject))
select new
{
Student = student.StudentName,
Subjects = string.Join(", ", classes)
})
.ToList();
Or, you can subquery with let. This will have noticeably slower performance against larger lists than the other solution, but it should be fine in the database.
var studentsAndCurrentSubjects = (
from student in lstStudents
let enrollments = lstEnrolled.Where(x => student == x.Student).Select(x => x.Subject)
let drops = lstDrops.Where(x => student == drop.Student).Select(x => x.Subject)
let classes = enrollments.Except(drops)
select new
{
Student = student.StudentName,
Subjects = string.Join(", ", classes)
})
.ToList();

How to update AmountDue value by InvoiceId in XERO API using C#

I am getting the list of Invoice details by Invoice Id.
Now i want to update AmountDue by respective Invoice Id.
i tried by below code:
ByInvoiceId.AmountDue = Convert.ToDecimal(100.00);
public_app_api.Invoices.Update(ByInvoiceId);
but..Error as
"A validation exception occurred"
What's the reason behind and How to solve this?

There are a number of ways to change the amount due on an invoice, however changing the value of the property directly is not one of them.
The amount due on an invoice is driven by the totals of the line items on the invoice minus the total of payments and allocated credit. One way to change the amount due is to change the values of your line items or add/remove some line items. You won't be able to change the invoice if it has been paid/partially paid.
Another way you could change the amount due on an invoice is to add a payment against the invoice or allocate credit from a credit note, prepayment, or overpayment to the invoice

In addition to MJMortimer's answer.
You can't change the line amounts on an AUTHORISED invoice via the c# API. You have to VOID the invoice and create a new one. You can however update DRAFT and SUBMITTED ones by updating the line items.
EDIT: Here is some code to help you. This is create invoice code, but amending one is essentially the same.
public XeroTransferResult CreateInvoices(IEnumerable<InvoiceModel> invoices, string user, string status)
{
_user = XeroApiHelper.User(user);
var invoicestatus = InvoiceStatus.Draft;
if (status == "SUBMITTED")
{
invoicestatus = InvoiceStatus.Submitted;
}
else if (status == "AUTHORISED")
{
invoicestatus = InvoiceStatus.Authorised;
}
var api = XeroApiHelper.CoreApi();
var xinvs = new List<Invoice>();
foreach (var inv in invoices)
{
var items = new List<LineItem>();
foreach (var line in inv.Lines)
{
decimal discount = 0;
if (line.PriceBeforeDiscount != line.Price)
{
discount = (decimal)(1 - line.Price / line.PriceBeforeDiscount) * 100;
}
items.Add(new LineItem
{
AccountCode = line.AccountCode,
Description = line.PublicationName != "N/A" ? line.PublicationName + " - " + line.Description : line.Description,
TaxAmount = (decimal)line.TaxAmount,
Quantity = 1,
UnitAmount = (decimal)line.PriceBeforeDiscount,
DiscountRate = discount,
TaxType = line.XeroCode,
ItemCode = line.ItemCode
});
}
var person = inv.Company.People.FirstOrDefault(p => p.IsAccountContact);
if (person == null)
{
person = inv.Company.People.FirstOrDefault(p => p.IsPrimaryContact);
}
var ninv = new Invoice
{
Number = inv.ClientInvoiceId,
Type = InvoiceType.AccountsReceivable,
Status = invoicestatus,
Reference = inv.Reference,
Contact = new Contact
{
Name = inv.Company.OrganisationName,
//ContactNumber = "MM" + inv.Company.CompanyId.ToString(),
FirstName = person.FirstName,
LastName = person.LastName,
EmailAddress = person.Email,
Phones = new List<Phone>()
{
new Phone {PhoneNumber = person.Telephone, PhoneType = PhoneType.Default},
new Phone {PhoneNumber = person.Mobile, PhoneType = PhoneType.Mobile}
},
Addresses = new List<Address>
{ new Address
{
//AttentionTo = inv.Company.People.FirstOrDefault(p => p.IsAccountContact) == null
//? inv.Company.People.FirstOrDefault(p=> p.IsPrimaryContact).FullName
//: inv.Company.People.FirstOrDefault(p => p.IsAccountContact).FullName,
//AddressLine1 = inv.Company.OrganisationName,
AddressLine1 = inv.Company.Address.Address1,
AddressLine2 = inv.Company.Address.Address2 ?? "",
AddressLine3 = inv.Company.Address.Address3 ?? "",
Region = inv.Company.Address.CountyState,
City = inv.Company.Address.TownCity,
PostalCode = inv.Company.Address.PostCode,
}
}
},
AmountDue = (decimal)inv.TotalAmount,
Date = inv.InvoiceDate,
DueDate = inv.DueDate,
LineItems = items,
LineAmountTypes = LineAmountType.Exclusive
};
if (SessionContext.TransferContactDetailsToXero == false)
{
ninv.Contact = new Contact
{
Id = inv.Company.XeroId ?? Guid.Empty,
Name = inv.Company.OrganisationName
};
}
xinvs.Add(ninv);
}
var success = true;
var xinvresult = new List<Invoice>();
try
{
api.SummarizeErrors(false);
xinvresult = api.Invoices.Create(xinvs).ToList();
}
catch (ValidationException ex)
{
// Something's gone wrong
}
foreach (var inv in xinvresult)
{
var mminvoice = invoices.FirstOrDefault(i => i.ClientInvoiceId == inv.Number);
if (inv.Errors != null && inv.Errors.Count > 0)
{
success = false;
if (mminvoice != null)
{
var errors = new List<XeroError>();
foreach (var err in inv.Errors)
{
errors.Add(new XeroError { ErrorDescription = err.Message });
}
mminvoice.XeroErrors = errors;
}
}
else
{
mminvoice.XeroTransferDate = DateTime.Now;
mminvoice.XeroId = inv.Id;
mminvoice.XeroErrors = new List<XeroError>();
}
}
return new XeroTransferResult
{
Invoices = invoices,
Success = success
};
}

looping through a C# collections

i have a class and method
public class Datas
{
public string Name { get; set; }
public int Value { get; set; }
}
public void Funnel()
{
string commandText = "select sc.stagename, count(cs.stages_id) as StageCount from currentstage cs inner join stagesconfig sc on cs.stages_id = sc.stages_id group by cs.stages_id,sc.stagename";
string constrings = WebConfigurationManager.ConnectionStrings["Data"].ToString();
SqlConnection myConn = new SqlConnection(constrings);
SqlCommand myComm = new SqlCommand(commandText, myConn);
myConn.Open();
List<Datas> fruitinfo = new List<Datas>();
SqlDataReader reader = myComm.ExecuteReader();
if (reader.HasRows)
{
while (reader.Read())
{
fruitinfo.Add(new Datas
{
Name = reader.GetValue(0).ToString(),
Value = Convert.ToInt32(reader.GetValue(1))
});
}
}
how do you loop through fruitinfo list saving it in form of an array.the array must be similar to this form.intended to replace the items in Data parenthesis with fruitinfo looped list
Data = new Data(new object[]
{
new object[] { "Website visits", 10000 },
new object[] { "Downloads", 5000 },
new object[] { "Requested price list", 2000 },
new object[] { "Invoice sent", 1000 },
new object[] { "Finalized", 500 }
}),

var myArray = fruitinfo.Select(x => new object[] { x.Name, x.Value }).ToArray();
And the use it with your Data-object.
Data = new Data(myArray);

var myArray = fruitinfo.Select(d => new object[] { d.Name, d.Value }).ToArray();

I am not too sure why you need to produce an array of anonymous objects, but you can use a dictionary.
private static void Funnel()
{
var datas = new List<Datas>
{
new Datas { Name = "Website visits", Value = 10000 },
new Datas { Name = "Downloads", Value = 5000 },
new Datas { Name = "Requested price list", Value = 2000 },
new Datas { Name = "Invoice sent", Value = 1000 },
new Datas { Name = "Finalized", Value = 500 }
};
var data = datas.ToDictionary(datas1 => datas1.Name, datas1 => datas1.Value);
foreach (var item in data)
{
Console.WriteLine(string.Format("{0}, {1}",item.Key, item.Value));
}
var arry = data.ToArray();
foreach (var item in arry)
{
Console.WriteLine(string.Format("{0}, {1}", item.Key, item.Value));
}
}

C# Use delegate to replace if else code

I know this method is working well. However I reused most of the code and it looks ugly... It should be possible to remove the if else using delegate. Any thoughts?
public IHttpActionResult TimeDatawithUserandServer(string name, string group)
{
List<Model> res = new List<Model>();
//group 1 is Server type
if (group.Equals("1"))
{
var realName = name.Replace("-", ".");
IQueryable<Overalldata> UserData = db.Overalldatas.Where(x => x.Server.Equals(realName));
var groupedUserData = UserData.GroupBy(x => new {x.EventDate, x.User}).ToList();
res.AddRange(groupedUserData.Select(item => new Model()
{
Count = item.Count(),
Date = item.Key.EventDate.ToString("yyyy-MM-dd HH:mm:ss"),
Name = item.Key.User
}));
}
//group 2 is User type
else
{
IQueryable<Overalldata> Serverdata = db.Overalldatas.Where(x => x.User.Equals(name));
var groupServerData = Serverdata.GroupBy(x => new {x.EventDate, x.Server}).ToList();
res.AddRange(groupServerData.Select(item => new Model()
{
Count = item.Count(),
Date = item.Key.EventDate.ToString("yyyy-MM-dd HH:mm:ss"),
Name = item.Key.Server
}));
}
return Ok(res);
}

You could do it this way:
public IHttpActionResult TimeDatawithUserandServer(string name, string group)
{
var getName = group == "1"
? (Func<Overalldata, string>)(od => od.Server)
: (Func<Overalldata, string>)(od => od.User);
var realName = group == "1"
? name.Replace("-", ".")
: name;
var UserData = group == "1"
? db.Overalldatas.Where(x => x.Server == realName)
: db.Overalldatas.Where(x => x.User == realName);
var groupedData =
UserData
.ToArray()
.GroupBy(x => new { x.EventDate, Name = getName(x) })
.ToArray();
var res =
groupedData
.Select(item => new Model()
{
Count = item.Count(),
Date = item.Key.EventDate.ToString("yyyy-MM-dd HH:mm:ss"),
Name = item.Key.Name
})
.ToList();
return Ok(res);
}

Without Delegates
Your code can simply be refactored to following and relieved from repetition:
public IHttpActionResult TimeDatawithUserandServer(string name, string group)
{
List<Model> res = new List<Model>();
var groupedData = group.Equals("1") ? FetchServerData(name) : FetchUserData(name);
res.AddRange(groupedData.Select(item => new Model()
{
Count = item.Count(),
Date = item.Key.EventDate.ToString("yyyy-MM-dd HH:mm:ss"),
Name = item.Key.Server
}));
return Ok(res);
}
private GroupedDataType FetchServerData(string name)
{
var realName = name.Replace("-", ".");
var UserData = db.Overalldatas.Where(x => x.Server.Equals(realName));
return UserData.GroupBy(x => new {x.EventDate, x.User}).ToList();
}
private GroupedDataType FetchUserData(string name)
{
var Serverdata = db.Overalldatas.Where(x => x.User.Equals(name));
return Serverdata.GroupBy(x => new {x.EventDate, x.Server}).ToList();
}
Please replace the GroupedDataType with the appropriate type in the two methods above and in the code below.
With Delegates
Using Reflection we find the correct field (or property) and then compare the value as in the code below:
public IHttpActionResult TimeDatawithUserandServer(string name, string group)
{
List<Model> res = new List<Model>();
var groupedData = GetGroupedList(group, name);
res.AddRange(groupedData.Select(item => new Model()
{
Count = item.Count(),
Date = item.Key.EventDate.ToString("yyyy-MM-dd HH:mm:ss"),
Name = item.Key.Server
}));
return Ok(res);
}
private static IEnumerable<GroupedDataType> GetGroupedList(string group, string name)
{
var filteredList = db.Overalldatas.Where(dbData => Filter(dbData, group, name));
return filteredList.GroupBy(x => new {x.EventDate, x.User}).ToList();
}
private static readonly Func<ODType, string, string, bool> Filter = (ode, group, name) =>
{
var objType = overallDataElement.GetType();
var field = objType.GetMember(group)[0];
return (field != null)
&& ((FieldInfo) field).GetValue(ode).ToString().Equals(name);
};
ODType is Type of the elements in of Overalldatas list and ode is overalldata list's one single element.

I agreed with a comment made by lc who suggested running this through a code review.
There are some potential anti-patterns in your code
The group parameter is an example of control coupling
The control coupling is utilized via the if statement. For me, this is a clear sign that the method should be broken into separate methods.
I would also like to call attention to the Overalldatas collection. It's name is suspicious which leads to other questions including "Is this data object trying to do too much?". But I won't really touch and this as it's less relevant to your question and my answer.
That said, my answer is that you should have two methods, one for "Server Type" and one for "User Type". I realize this pushes that "group" check elsewhere, but that can be solved later and today the intent of your methods will be MUCH clearer.
public IHttpActionResult TimeDataByUserName(string userName)
{
List<Model> res = new List<Model>();
IQueryable<Overalldata> Serverdata = db.Overalldatas.Where(x => x.User.Equals(userName));
var groupServerData = Serverdata.GroupBy(x => new {x.EventDate, x.Server}).ToList();
res.AddRange(groupServerData.Select(item => new Model()
{
Count = item.Count(),
Date = item.Key.EventDate.ToString("yyyy-MM-dd HH:mm:ss"),
Name = item.Key.Server
}));
return Ok(res);
}
public IHttpActionResult TimeDataByServerName(string serverName)
{
List<Model> res = new List<Model>();
IQueryable<Overalldata> UserData = db.Overalldatas.Where(x => x.Server.Equals(serverName));
var groupedUserData = UserData.GroupBy(x => new {x.EventDate, x.User}).ToList();
res.AddRange(groupedUserData.Select(item => new Model()
{
Count = item.Count(),
Date = item.Key.EventDate.ToString("yyyy-MM-dd HH:mm:ss"),
Name = item.Key.User
}));
}