Sorting A List Of Objects?
Mar 16, 2012Suppose I have:
Public Class myClass1
Dim foo As String
Dim bar As String
[code].....
Suppose I have:
Public Class myClass1
Dim foo As String
Dim bar As String
[code].....
I have a group of objects stored in an arraylist. These custom type objects have a number of properties from their underlying class . I want to use one of the properties to sort the array. I cannot determine which Array.Sort method to use.
I want to sort based on an integer property. Virtually every example I can find involves sorting strings.
So, assume the Objects have the following properties.
Obj.name as string
Obj.ID as integer
Obj.Alive as boolean
The objects are kept in an arraylist called FriendsOfMine.
I want to be able to order the list by Obj.ID, both ascending and descending in value.
what the point of a Generic.LinkedList is in Visual Basic .NET 2010.I've heard that I can save sorting time with such a list, since it somehow sorts objects as they are added.How can I perform such sorting with this type of list?
View 1 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'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.
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]...
I'm trying to sort a List of objects with a generic comparison.I get an exception when the property on which I'm sorting happens to be null in one of the objects.VB.NET 2.0, web.i've read several posts on this exception, and still don't get it.[code]It is true that this only happens on properties which happen to be null somewhere in the list.Sometimes I sort on other properties which happen to always be always non-null (using a different, but similar, comparison method), and this technique works just fine.I've tried to implement the CompareTo for both IComparable and IComparable(of FollowupSurvey) so I could capture this exception while debugging, but netiher actually get invoked (despite what it seems like the exception is telling me). At this point, I don't have a CompareTo in my FollowupSurvey object; thus, it's using Object's.It doesn't seem as if I can really help if the base CompareTo doesn't reutrn 0.anyone have any idea what this exception really means, and how to make sorting work properly?
View 2 RepliesI have a list (i.e. Dim nList as new List(of className)). Each class has a property named zIndex (i.e. className.zIndex). Is it possible to sort the elements of the list by the zIndex variable in all of the elements of the list?
View 4 RepliesI have a simple type like:-
[Code]....
if I have a list of type top_params then how can i sort the list based values in the k_sig_level field?
I need two seperate lists, which every item is Integer, String, Bitmap - and one which every item is Integer, String String. However I don't know how to do this, or even where to look - I've googled for custom objects and custom object lists. What I'm trying to do is this.Custom Object1 is Integer, String, Bitmap Custom Object2 is Integer, String, String
In one thread I'll be adding items to List1(Of Object1), and processing them, and adding the results to List2(Of Object2), however I need to be able from other threads to look at the list and say only give me the items where Integer = (my thread ID), is this possible? Any help, or even links to information that would be relevant to this request would be helpful?
I have a list of instruments and I need to sort them to the following requirement.
order by:
cash
securities in alphabetical order
managed funds in alphabetical order
I have a list of instrument which has properties name and type, I've managed to sort alphabetically by name.
Instruments.Sort(Function(x, y) String.Compare(x.Name, y.Name))
Instruments.Sort((x, y) => string.Compare(x.Name, y.Name));
how we can sort a listview on column wise in a simple way?
View 2 RepliesI had a need to mark a listview row if filenames were duplicates for n number of characters from the left. I wrote the following but it smacks of VB6.[code]...
View 5 RepliesI have a list going into a repeater, sorting with jquery sortable(), and then need to put the sorted list into a session variable. I cannot seem to figure out how to get the sorted values back into a list.[code]...
View 1 RepliesI have a slightly odd problem that I think is most likely due to an act of foolishness on my part, but for the life of me I (and other members of my team) can't see it.I have an object that contains a generic list property which I would like to sort. I have written a comparer class to do this for me and I am calling it in the following way:baseObject.ListOfThings.Sort(new ThingComparer()I have debugged into my compare function and it is returning the right values.However After the sort call, the list remains unchanged. Have I missed something obvious, or is there something else I need to do.EDIT: Yes I was being a fool, and the property returning a list was recreating it from scratch each time it was accessed
View 4 RepliesI have a List of FileInfo objects that I want to sort by creation date & file size. Is there a way to do that?
View 5 RepliesI am using the code from hereevelopment/vbnet/code/370426 to sort my listview items. But I want something more 'dynamic': when I click on a header column, I want that it changes the sorting based on the column that has been clicked. here is my code:
'Classes usadas
Imports System.Math
Imports System.IO
[code].....
I would like to sort a list of strings which represent paths. The sort result will do have a hierarchical order. What I mean is: for each directory path, I want to list all files in that path (alphabeticaly or not doesn't matter) in first time. Then, each subdirectory path will be listed. For each subdirectory, I want all files..
[Code]...
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 have been learning how to sort a list using lambda functions
excessPop.Sort(Function(f1, f2) f1.ID.CompareTo(f2.ID))
I am however struggling to sort a list using 2 parameters within a lambda function. The properties within my list that i need to sort by are Category and then by Cost. how to do this?
One displays a list of contributors for a charity and the amount given in a text box.However iv created another button but i need this to sort the list of names to just display the names and in alphabetical order.
[Code]...
I need to sort a list (of person) to person.Age within person.Department. f I user personlist.sort with a comparer for Age and then sort again with a comparer for Department, the sequence of age is destroyed.
View 1 RepliesIn 2007 I created a program that reads weather data into a listview. When a user clicks on the column header it fires off the column click event handler which calls the Sort Wrapper function. The Sort wrapper will re-order items either in ascending or descending order.
I have never been able to get negative integers to sort properly. I have created a stripped down listview program with a few numbers in the grid for testing. (see attached program zip file).When you run the program, click on the column header that says "Val" and you will see right away that the numbers do not sort correctly.
I have a lists of different custom classes and each must be sorted severals times before the algorithm is complete. For each sort I wrote a comparer. Sofar so good. Everything works. But: By now I have abou a dozen different comparers in more than one class and it is still getting more. I wonder if there is a way to limit the number by writing a new general function that can be used to sort all lists without the need for a specific comparer.Below is what I've got so far. But it does not work.
"System.Collections.Generic.List(Of ClassA)" can not be converted into "System.Collections.Generic.List(Of Object)."
[code].....
I'm looking for a simple and efficient way to sort up to 60,000 strings that are 3000 chars long in reverse order and save them back out to a text file.
I originally thought of a doubly linked list, but then I realized that we aren't privileged enough to have pointers.
Is there some other way I can create an efficient linked list without pointers?
So I'm working on this school project where I'm supposed to add names and laptimes from textboxes to a list. I've got that sorted out with some help from Shaggy_Hiker (thanks!). Now what I'm trying to do is get the best laptime from the list of entries and display that in a label. I also want to sort the list by laptimes in ascending order, and I've tried the.Sort method without too much luck + all entries with a laptime over 60 min should be disqualified.
(I'm thinking of adding all of these to a seperate list which I've named feilreg, but right now all entries that doesn't meet the right criteria like empty textbox, negative laptime and so on gets saved to that list. I'd like to make it just entries over 60 min) I also can't seem to figure out why a laptime of say '32.45' won't register, it has to be with a comma like '32,45'. I've got a function in my class 'Rundetid' to format the output to two decimals maximum.
[Code]...
I'm using the following code to sort a List(of Class) using LINQ. It works fine, but I'm wondering if there is a better way to do it. I'm basically taking one list, applying LINQ to it, then using the result to create a second list in the sorted order. Can I do this without creating a second list? Here is my sample
' KeyMatch is my Class Variable
' mMatchList is the Unsorted List
'
[code].....
I am using a list to keep track of a number of custom Row objects as follows:
Public Rows As List(Of Row)()
Row has 2 properties, Key (a String) and Cells (an ArrayList).
I need to be able to sort each Row within Rows based on a developer defined index of the Cells ArrayList.
So for example based on the following Rows
Row1.Cells = ("b", "12")
Row2.Cells = ("a", "23")
Rows.Sort(0) would result in Row2 being first in the Rows list. What would be the best way of going about implementing this?
I'm using a Listview in VirtualMode, so I can 'add' a lot of files almost instantly. A Listview in VirtualMode does not allow sorting, so I need to sort the data myself. The data is stored as a List of Structure (it's faster to load than a List of ListViewItem). The code below works fine, but I need to sort based on multiple variables in the Structure. Code:
View 2 Replies