.net - Searching A List Of Objects In An Object List Using Linq?
Dec 22, 2010I have 2 classes
Public Class Shipper
Public Property ShipperID As Long
Public Property CreateDate As DateTime
[Code].....
I have 2 classes
Public Class Shipper
Public Property ShipperID As Long
Public Property CreateDate As DateTime
[Code].....
I'm trying to create a list of days(integer) from a list of dates(date).
I tryed to do this....
[Code]...
Limited to using v2.0 of .Net framework (we use VB.net) due to environmental constraints on our servers.I've got an ASP.net webpage which pulls data from a webservice that performs checks on user accounts in active directory. Operators can check multiple accounts at one time using the web interface. The webservice returns a list(of AccountCheck) objects which themselves contain single properties like username, email address, and List(of AccountError) objects which contain multiple properties.[code]What I want to do is using some kind of repeater, create multiple panels or divs which contain labels showing the username, email etc, and a gridview which has the accounterror list bound to it to show all the errors. The users could be checking 2, 5, 7 accounts at once, and is dynamic.
View 2 RepliesI would like to create list of child objects from list of parent object. Like If i have list of bookingroom which has one member room then i would like to create list of room from it.
eg. code:
Dim BookingRoomList As List(Of BookingRoom) = New List(Of BookingRoom)
Dim RoomList As List(Of Room) = New List(Of Room)
BookingRoomList = BookingRooms.FillGrid()
[Code]....
Is there any short cut method instead of iterating over for earch?
I have list object and I need to check id in a comma separated string using LINQ in VB.NET, something like this:
dim strId as String = "1,2,3,5,"
dim myList = from objmylist where objmylist.id in (strId)
I have a list of objects, each with 2 relevant properties: "ID" and "Name". Lets call the list "lstOutcomes".I need to check the list for duplicates (meaning object1.ID = object2.ID, etc.) and set a flag (valid = false, or something) if there is at least one duplicate. Also, it would be nice to send a message to the user mentioning the "Name" of the object, when it fails.I am sure I will need to use the Group By operator to do this, but I am not used to doing that in LINQ, and the examples out there are just not helping me. This article seems to be close to what i need, but not quite and it's in C#.
Here is a starting stab at it...
Dim duplist = _
(From o As objectType In lstOutcomes _
[code]......
help?
I have a query that 'selects' object of a type:
Dim l as IList(Of Foo) = (From dataRow As DataRow In table.Select()
Where CStr(dataRow("Column1")) = "A"
Select New Foo(CStr(dataRow("Column1")), _
CStr(dataRow("Column2")))).ToList()
What's happening is that if i set a break-point to the constructor of Foo and step, the constructor is hit and the parameters are loaded with the arguments. However, l has empty Foo objects (the members in every object are Nothing). What could be happening here?
I have
Dim objectsList as List(Of Object) = GetAllObjects()
' Filter from Objects just Persons '
Dim peopleList as List(Of Person) = ???
What is the most efficient and effective LINQ expression to do it?
EDIT
1 Dim selectedObjects As List(Of Object) = GetAllObjects()
2 Dim selectedPeople As IEnumerable(Of Person)= selectedObjects.OfType(Of Person)
3 Dim people As List(Of Person) = selectedPeople.ToList()
Error on 3:
Value of type
'System.Collections.Generic.List(Of
System.Collections.Generic.IEnumerable(Of Person))' cannot be
converted to
'System.Collections.Generic.List(Of Person)'.
I figure I should use 'Aggregate' but apparently I am getting it wrong First I get a list of my Entity objects Dim employers As List(Of myEntity) = (New XXXX()).getZZZ(userName, userType) Then I figured this would be a way to put all the names in a string Dim names as String = employers.Aggregate(Function(current, [next]) current.Name & " " & [next].Name)
[Code]....
Basically, I am trying to write a LINQ to Objects statement where the relationship is a grandparent, parent, child relationship. (You could also call it a Master Detail relationship.)
In Legacy code here is a simplified version what I am trying to accomplish.
Dim coverages As New List(Of Coverage)
Dim coverage As Coverage
For Each rl In oClaimsPolicy.RiskLocations
coverage = New Coverage
coverage.Level = "Location"
[Code] .....
If is it not clear one Location can have many Items and one Item can have many Coverages. I basically want to list the items and show the relationship between grandparent (Location), parent (Item) and child (Coverage).
I am having so trouble with the ToUpper() procedure with strings. I am using LINQ to find unique values in a list of objects. In that whole process I set the values to compare to all lowercase in order to get a proper list. My goal is to populate a dropdown list with the values. I'm attempting to set the first letter of of the string to uppercase and keep the rest lowercase however the toUpper() procedure is not working?
Private Function FixCase(ByVal strIn) As String
Dim strOutput As String
Dim intStringLength As Integer = strIn.Length - 1
strOutput = strIn.Substring(0, 1)
[code].....
I don't know if this is doable, maybe with Linq, but I have a List(Of MyType):
Public Class MyType
Property key As Char
Property description As String
End Class
And I want to create a Dictionary(Of Char, MyType) using the key field as the dictionary keys and the values in the List as the dictionary values, with something like:
New Dictionary(Of Char, MyType)(??)
Even if this is doable, internally it will loop through all the List items, I guess?
I save the client data into an array list. How to find part of data(currentIP) inside the array list(clientList) with fast method? [code]
View 1 RepliesOK - for starters - I'm not even sure that the title of this thread accurately describes what I want to do - but I had trouble verbalizing it. So I will give this a try: In my application, I have a custom object, call it myObject. In addition, I have another custom object called myObjectList which is basically a List(Of myObject).
Up until this point, all of the functions that I have been working with in my BLL and DAL have been shared - I haven't needed a specific instance of my object thus far. I currently need to write a function that finds a particular myObject within myObjectList and returns to me myObject. I know that the List(Of T) has a find method, but from what I have read so far - I don't think it is what I want (doesn't it return true or false? -and also, do I need an existing object to pass to it to see if it is in the list?)
[Code]...
Is it possible to find a complete object in list of objects?
how to find x in list1 if it exists without comparing a single property like ID ?
Is there a simple way to remove Objects from a List by using a specified value?I add 2 persons to a List, how can now I remove a person by a name without using any Loops? (if possible)
[Code]...
I have a combo box that is populated with a list of objects (corresponding to all employee rows from a database that meet the criteria IsTech). These are not entity objects though, I have created my own class that stores the member values of each row from the DB. I have set the DisplayMemberPath to EmployeeId so the Combo box display the EmployeeId ( an integer ) member of my object. Ie. right now there are only 2 IsTech employees in my DB so the combobox displays the numbers 3 and 8 ( their EmployeeIDs).
[Code]...
I have a list of objects, each object has a score attribute,The list of scores needs to be combined on the player ID to become a totaled score or series. My current thought process is to For Each through the list of individual games, and add the score attribute to a new list of scores with the same objects. So one list would be like:
clsGame(ID Number, Sore)
dim ScoreList as list(of clsGames)
ScoreList.Add(New clsGame(11, 244)
ScoreList.Add(New clsGame(11, 333)
ScoreList.Add(New clsGame(11, 444)
Then go through combining on like ID's to make a new list of games, that would actually be the series.
Dim SeriesList as new list(of clsClasses)
For each game as clsGame in ScoreList
'cycle through the list of series seeing if an ID matches, if so add the score onto that ID
Else
[code]....
Now I don't know how to add the player if its not in the seiries list without doing a heck of a lot more for each statements. If I add it after the end if then it will be added even if it is in the list..I tried playing around with List.Contains method, but I could only see if it contaned the exact same values i.e
SeiresList.Contains(game)
and because the scores are different (series vs single game) it wouldn't match, and I don't know how to see if it contains an object with just one of the attributes the same...
I am using LINQ - VB.Net I want to filter my List object by passing String object in the where.
Dim _permittedTransactionCodes As List(Of String) = Nothing 'String object
it is populated with data.
Dim tap100transCodeInfos As List(Of Tap100transCodeInfo) = _dal.GetActiveTap100transCodeByHdrScreenCde(UCase(screenId), "TRAN_CDE")
i am trying something below, but not getting the filtered results
tap100transCodeInfos.Where(Function(x) _permittedTransactionCodes.Contains(x.TranCde))
I'm trying out some LINQ expressions and can't get them to work with the List class. Basically I want to be able to sort a list of custom objects by property type, however the C# LINQ syntax is KILLING me and I can't figure out how to convert it to VB
Class Foo
Sub New(Name As String, Position As Integer)
Me.Name = Name
[code]....
I made an object that has several properties one of which is an integer.
I put all the objects into a list, and I wish to sort that list by the integer property, with the object with the highest property at item 0, with the object with the lowest property at the highest item # ( count -1).
I made the list of that item, as in
Dim GameList as new list(of clsGame)
And I wish to do something like the following
GameList.Score.Sort()
What is the syntax to do that? I looked up the MSDN and didn't really understand what it was trying to say
I have a school project i am working on wich i am to build a program that randomly generates 500 alpha-numeric numbers (license plate numbers). the program needs to be able to search the 500 numbers and based on given criteria (a text box) that you put in return the matching results to another listbox. I got the 500 plate numbers to generate on form load but have been searching thru my textbook and cant seem to figure out how to take the imput from the text box and search the list box. Not asking for a ton of help but just a point in the right direction. i attached the assignment i was given from instructor.
[Code]...
Dim tenItem = From t In _InvalidFeeList _
From i In ItemCount _
Where t.FeeCode <> i.FeeCode _
[Code]....
I am getting "Can not convert to System.generic.list" error. I look all over for this error and it seem like my code should work for example here
edit: I think i should explain what I'm trying to do here. I want to compare two object list and select the object from the InvalidFeeList if the FeeCode is not equal to the object in ItemCount FeeCode and take the first 10 objects from the InvalidFeeList.
I'm having a bit of a 'brain doner' moment here
I have a list of Objects. Each of these Objects contains a list of other Objects (pseudo code) :-
Private Structure Object1
dim Name as string
dim ListOfObject2 as List(Of Object2)
[Code]....
I need to sort the list of Object1 by the Value in Object2. I have a comparison class which sorts Object2 by its Value nicely.
After reading all the examples for list of T exists and Find and find first, none show how to handle multi-property objects. Below is bare bones example maybe someone could flesh out to show how this should be done.
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim DatePriceList As New List(Of DateAndPrice)
DatePriceList.Add(New DateAndPrice(Date.Parse("1/1/2000"), 10.12))
DatePriceList.Add(New DateAndPrice(Date.Parse("1/2/2000"), 11.12))
[Code]...
y have this class
Private Class MyClass
Public Property propertyOne() as String
Public Property propertyTwo() as String
[code].....
I have these objects:[code]Using LINQ I need to take a List(Of MakeInfo) and a List(Of ModelInfo) and aggregate the StockInfo from ModelInfo into the List(Of MakeInfo).So for each MakeInfo I will have a total count of all stock where MakeInfo.Name = ModelInfo.Make, and also a minimum price.I think it's going to be something like this, but I'm having trouble accessing the nested object and not sure if it's going to be possible with a single query.[code]
View 2 RepliesHow can I get a new distinct list from an existing list using LINQ? This is what I have so far and it is not distinct but does give me a new list.
Dim tmpQryColumn = (From a In _allAudits
Select New CheckBoxListItem
With {.Id = a.AuditColumn, .Name = a.AuditColumn}
).Distinct()
_columnList = New List(Of CheckBoxListItem)(tmpQryColumn)
How can I get a new distinct list from an existing list using LINQ? This is what I have so far and it is not distinct but does give me a new list.
Dim tmpQryColumn = (From a In _allAudits
Select New CheckBoxListItem
With {.Id = a.AuditColumn, .Name = a.AuditColumn}
[code]......
I have two generic lists, named ListA and ListB. Both ListA and ListB could potentially have duplicate items. What I would like to do is use LINQ to grab the items in ListB that are not in ListA, but I'm unsure how to do so.
View 8 Replies