Create Local Copy Of A List To Be Able To Change Elements Only In New List?
Oct 26, 2011
This is probably a really basic question - but I have a list of items (custom objects) being passed from one winform (.net 3.5) to another. I want to create a local list to store changes that only get persisted if the user clicks save. Currently if the user clicks cancel - the changes are still applied in the first form because I assume the objects are reference type.I have the save working as it calls a service layer to do the save and then refreshes the other form - but not the cancel.
How would I create a list of elements in VB.NET, save it to a .dat file, and make Ruby re-create such list (as an array) with such elements (they will be strings, booleans and integers)?
I have to collection objects as follows Dim List1 As New List(Of clsTimesheet_Detail) Dim List2 As New List(Of clsTimesheet_Detail) I have filled the List1 and now want to make an independent copy to the List2
II am trying to create a toggle button that switches a list to a range and then back to a list if needed. I am able to get it to do both but when I add an item to the list, convert to a range and then convert back to a list it leaves off the last items I entered.I tried to work in a code to select all cells but I must not be putting it in the right place.This is what I have so far:
i am trying to create a list of list in that i would like to work on multiple accounts at the same time. lets say i have 5 accounts. every account has a seperate name. each account has a few fields. so i though of having a list of bookkeeping (with 5 accounts) and a list of accounts (with expense, income, tax, status, etc as fields). [code] and if the idea of using list of list works how do i loop through both lists.
I 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?
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} ).Distinct() _columnList = New List(Of CheckBoxListItem)(tmpQryColumn)
I am able to only add controls that are of type TextBox. My question to you is, can I create a List to hold more than one control type or do I have to create a list for each control type?
I got a list of objects. Each object has a property called Z (integer).There will come a point during run-time I will want to re-arrange such objects in my list depending on their Z property. The objects with lower Z go first in the list, and the ones with higher will go last.I have thought of a couple things, like making a new List, then loop through each object in the original list as many times as the amount of objects such list has (so if it has 10 objects, I would loop 100 times), and each iteration will check the Z values. When a cycle is done (for every 10 iterations), I will remove the object with the lowest Z number in cycle and add it to the new List. And so on until the 100 iterations are done.
I have a List of a custom class (barData) that I need to remove elements form based on a date.
The bardata class holds data of stock price information.[cod]e...
Is there a way to do it without looping through each bar as I may have 2000 plus bars for each stock and may have 2000+ plus stocks to look at. It can be done by looping but it is slow.
I would like a function generate all of the k-combinations of elements from a List of n elements. Note that I am looking for combinations, not permutations, and that we need a solution for varying k (i.e., hard-coding the loops is a no-no).
I am looking for a solution that is a) elegant, and b) can be coded in VB10/.Net 4.0.
This means a) solutions requiring LINQ are ok, b) those using the C# "yield" command are not.
The order of the combinations is not important (i.e., lexicographical, Gray-code, what-have-you) and elegance is favored over performance, if the two are in conflict.
(The OCaml and C# solutions here would be perfect, if they could be coded in VB10.)
I am creating a dynamic clone method to be used in my custom classes. I want the clone function to be completely generic, so I do not have to make any changes when I add new properties to the class. I am having an issue with regards to making a deep copy a property that is a List. sample code that will enable me to identify with reflection that a property of my class is a List, and then more importantly the code to loop through the the List elements and copy of each of them. I have been able to identify a property as a List by using the NameSpace of the property type, but I'm not a big fan of that method. Either way, I have yet been able to dynamically loop and deep copy the elements of the property that's a List using reflection.
I'm making a bot to auto-reply to my PMs on a website, and I'd like to get all of the HTML elements with a class name 'InboxRow'. I can get the HTML element one at time, but the problem is that these will be dynamic, so the id and amt. of them will always change, so I want to put them in an array, where I can call each one up and perform the rest of my code for it. I just can't seem to be able to figure out how to find all the HTML elements with the class name and put them in an array, and I can't seem to find any tutorials online
Is there a succint way in vb.net to create an array or similar of each of the properties in a list?
E.g. If I have a list of 'a' and each 'a' has a property 'b', I want to create an array which contains all the 'b's, in the same index positions as the original list.
I have a user defined structure in a list that I am trying to change the value for in an individual element within the list of structures. Accessing the element is not a problem. However, the compiler complains
"Expression is a value and therefore cannot be the target of the assignment"when I try to update the value.For example:
Public Structure Person Dim first as String Dim last as String Dim age as Integer
I need to set up a list consisting of arrays of two elements. Simple, right?
Like: (code snippet):
Dim strDataPoint(1) As String '2-element array Dim lBiasCurve As New List(Of strDataPoint) 'list of 2-element arrays Dim lPwrCurve As New List(Of strDataPoint) 'another list of 2-element arrays
But this gives me an error msg on 2nd and 3rd line: type strDataPoint is not defined....
I'm trying to copy the elements from a List(Of Frequency) where Frequency is a custom class I have made. Everything in the other places seems alright but the problem seems to be with the copying, where it still references the original table, so changing the values of one changes the original. I've tried the List.CopyTo() method and tried converting to and array with List.ToArray and then using Array.Copy but it seems they always change the original. I've also tried a for loop and create and New instance of the classes but that doesn't work either. What I'm using it for is to pass the List(Of Frequency) to a new Task to do multitasking(), if anyone can think of a better method to pass a List(Of Frequency), or an array to to a task and have it not change the original.
Do List's hold the instances of a variable element or just the pointer to the the variable element? My application uses a list of elements, which can be re-ordered at any time, but I need to maintain another list of pointers to those elements, so that the element pointers can be used to access any element irrespective of their order in the main list? the difference between a pointer or a variable in the contect of list elements?
I have got an xml document which looks something like this.
<Root> <Info> </Info> <Info>
[Code]...
How can i write a linqToXML query so that it returns me an IEnumerable containing each child element, in this case all five child elements of , so that i could iterate over them. The order of child elements is not definite, neither is number of times the may appear.
I have a string with xml data.Dim appManifest As String = New System.IO.StreamReader(Application.GetResourceStream(New System.Windows.Resources.StreamResourceInfo(e.Result, Nothing), New Uri("AppManifest.xaml", UriKind.Relative)).Stream).ReadToEnd()
I use the removeRange function to remove a couple elements from a list, but the Count of the list seems to be intact, so I assume it didn't work the way I expected it too.... so, how do you remove elements? I mean, reduce the list's Count value ultimately.
