I have class called "Employee" and I have a class called Department. They have an association. I need to create a colleciton of employees with the creation of a Departmant. I know how to do with using "private" member _AllMyEmployees. But I need to expose this private member using properties. therefore how do i covert thsi private member to a property? [code]
View 2 RepliesI've reviewed the links that were offered and don't find an answer. Neither has a lot of searching helped, probably because I can't think of a reasonably short way to ask the question. I hope that I've at least found the proper forum and category.
In my VB 2010 code, I've defined a structure that has about 30 elements. I want to sum the properties (they are all singles) of two members of the corresponding collection. I understand that I can do something like:
member1.property1=member2.property1+member 3.property1 for the entire set of properties of member2 and member3 to produce a completely defined member1 What I wonder is whether or not there is a way that uses fewer lines of code - I know that I can't do:member1=member2+member3, for example.
I have some nested objects arranged like this:
Process
Persons
Workflows
Tasks
So you have one Process. Then multiple Persons can be added to and multiple WorkFlows can be added Process as well. Multiple Tasks can be added to each WorkFlow but I need a way to tie which Person is doing each task. I basically need a way that for each Person added to the Process it, in it's constructor, assigns a Person.ID property that can then be assigned into each Task's PersonID property...
Dim myProcess as New Process()
Dim myPerson as New Process.Person()
myProcess.AddPerson(myPerson)
[code]....
Thought I had got this sorted earlier but unfortunately not. A property in a class is a collection of objects.
[Code]...
Ive recently written a control called a ButtonRow in VB.NET that allows you to dynamically place buttons on it through a typed collection property. The property itself is tagged with the <DesignerSerializationVisibility(DesignerSerializationVisibility.Content)>. However it works really bad. First of all, whenever you add buttons to it and you delete the controlafterwards, the designer code file still have the buttons declared but without the aButtonRow to who's collection they would be added. Secondly, you cannot copy the controlfrom one form to another. It would just copy the ButtonRow object without the buttons
View 6 RepliesI'm working on a small project and got into some troubles trying to keep it OOP.I have a global variable:
Public Stations As New Microsoft.VisualBasic.Collection()
And 2 classess: Station & Unit:
Public Class Station
[code].....
I had read on pages like this
that when adding objects to a CheckedListBox, it takes the .ToString() function of each added object as the text string.
I added instances of SortedDictionary as this[code]...
I am trying to refresh my combobox when an item is selected and added the highlighted code as shown below; [code]Items collection cannot be modified when the DataSource property is set.
View 3 RepliesI have an object with a property that is a collection. When I point the PropertyGrid to the object it displays the ellipses for the collection. When I click it I get the generic collectioneditor. Of course the Add put fails because my collection is strongly typed. I need an example of how to create a collectioneditor that will create my collection's objects.
View 4 RepliesI have a combobobox on my form, and I use the following code to populate the data from SQL Server:
cbname.DataSource = DSAssetName.Tables(0)
cbname.DisplayMember = "IDWLNAME"
cbname.ValueMember = "FIDWID"
[code].....
I'm trying to create a datagrid with auto generating columns. Let's say my Collection is a property named Articles of my viewmodel of type ObservableCollection<ArticleWrapper>.
I bind now the ItemsSource to this collection:
<wpf:DataGrid ItemsSource={Binding Articles} />
The class ArticleWrapper is like this:
[c#]
public class ArticleWrapper
{
public ArticleConfigurationSet ArticleConfigurationSet { get; set; }
public string Description { get; set; }
[Code]....
But now my problem: I want to bind the displayed data to my ArticleConfigurationSet property. But I cannot change my ItemsSource Binding, because the SelectedItem property of the datagrid must be of ArticleWrapper (for command handling).
The datagrid should also look like this:
I have two tables "Person" and "Alias" in a one to many relationship. I have a DGV for "Person" and want to use a combobox for the Aliases. I also have a textbox and a button for the user to type the alias name and click the button to add the alias name to the combobox and update the dataset. I keep getting the "Items collection cannot be modified when the DataSource property is set." Error. But if i use a DGV instead of a combobox for aliases, I have no errors and everything works fine. If I remove the datasource property for the combobox it will not get populated with the data already entered, so how, or can I, set it up where the combobox gets populated when the form loads and able to add items to the combobox????
View 1 RepliesLike i want it to read the lines i have in the text file but i get an error Each time i press the button Why?
Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
Dim objreader As New System.IO.StreamReader("C:UsersJamesDesktopMusicas.txt")
Do Until objreader.EndOfStream
[code]....
Error:
Quote:
Items collection cannot be modified when the DataSource property is set.
Error line
Quote:
ListBox1.Items.Add(objreader)
During a code review I looked at set of repository classes (in vb.net). I am used to seeing these repository classes full of functions that return collections (among other things) of your domain objects. However, this repository had 1 public property and 1 private variable that looked something like this:
Private _item as Collection (of Customer)
Public Item as Collection (of Customer)
Get...
Set...
In the "Get", there is code that gets a the Customers from the DAL and loads it in the private _item. What would the benefits be in using a property (customerRepository.Item) instead of plain old function (customerRepository.GetAllCustomers)? The "Property" way looks odd to me but odd doesn't always mean wrong.
error in binding
Dadapter = New SqlDataAdapter(dat, conn)
Me.Dadapter.Fill(Me.Table)
bs.DataSource = Me.Table
DgvTire.DataSource = bs
txtserial.DataBindings.Add("text", Table, "serialn")
error: This causes two bindings in the collection to bind to the same property. Parameter name: binding
what should i do with this error?
I get the following string expression provided:"ChildObject.FullName" ...where ChildObject is an instance property on the MyObject1 type.ChildObject has a property named "FullName" and I want to sort a collection of type "MyObject1" based on this child properties "FullName" value.
I can do this all day long on properties directly on MyObject1 but I run into 2 challanges when doing it on a child instance and I can't get all the pieces working. The main 2 challanges are:
MyObject1 has a few different child property types so I can't hardcode the type for ChildObject. The string could be of any type.The sort expression is a String and not a known type.Above the value returned from the last line in the expression (if I run the code outsode the OrderBy method, does provide me the 'FullName' information I need. So the code must be close, but it still does not work.
Any ideas on how I can accomplish this? What I am trying to prevent is hardcoding a series of 'If' blocks on the child's type to then hardcode in its type to the sort or OrderBy method.
I have a custom collection, lets says COL, that derives from ObjectModel.Collection. I have my own collection editor that works fine when a property, of type COL, is Read and Write enabled. However, if I change the property to ReadOnly, the open editor button stops showing in the property grid. As a test, I override my custom editor with the CollectionEditor, and that worked fine. So, my question is, what check is the property grid making, that CollectionEditor passes but my collection editor fails?
View 2 RepliesI have several custom classes in a VB.NET (VS2008) project which are related to each other through generic list collections. The lower tier classes refer directly to some of the parent classes (to make it easier to refer backwards up the chain). My question is, is it possible to add the reference to the parent class when the item is added to a collection, when that collection is a property?
Below is some sampling of code to illustrate.
Public Class FlexServer
Private m_FlexLicenses As List(Of FlexLicense)
Private m_Modules As List(Of FlexModule)
Public Property FlexLicenses() As List(Of FlexLicense)
[code] .....
In the code above I have the FlexServer class which refers has two lists as properties, one for FlexLicense and one for Modules. The FlexLicense class has a property to refer back to the FlexServer class that "owns" it. In order to update this property in code, I have to add the FlexLicense to the FlexServer.FlexLicenses list AND set the FlexLicense.FlexServer property. What I am looking for is, is there a way (in the property definition or wherever) to both add the item to the list and alter it at the same time?
I have a class that has a readonly collection property - Its a list of extender providers that have been applied to the control.I've implemented a simple property descriptor for the collection so that the property can be expanded in the property grid to examine each entry.
When I select an extender provider and set it to false, I remove it from the collection. The GetProperties method of the type converter is requeried and the property grid refreshes.However, when I set an extender provider to true, and thus add it to the collection, GetProperties is not requeried.
Somehow, the property grid is making a distinction between adding to and removing from the collection. Or alternativly, its refreshing when an extender provider is added, but not when one is removed.
[Code]...
I am experimenting with a transition from my application built in VB6 to vb.net. I know, about time. At the same time, i am making changes and improving upon the original. One area that I am working on is within my employee class. very standard class, nothing fancy. One change I want to make though is allow for an employee to be assigned more than one work location. Employee has (is assigned) Stores. In reading about collections, it appears they are different in .net (as they should be), but I don't know what the sytax changes will be to implement my changes.
View 6 RepliesI am creating a User Control where I have a property called Items. Items is of type LibraryPanelBarItem Collection (custom class) which contains a collection of LibraryPanelBarItem objects. I would like to be able to add these at design time by using the Collection editor that VS uses for adding things such as treenodes/listviewitems. Ideally I would also be able to declaratively add them to the html syntax. I can get the Items property to show up but I get no intellisense to add the items between the opening and closing tags. [Code]
View 1 RepliesThe tables described herein both utilize composite keys. I have a parent table that stores eligibility information per "case". The child table stores eligibility information regarding each individual associated with the case. The child records are differentiated by pin number to make them unique in the child table only.
I am using NHibernate v3.1 with Fluent NHibernate v1.2, both acquired via NuGet packages. The entities are mapped in using the Fluent NHibernate auto-mapper functionality. Any custom mapping is done in the mapping override method for each entity.
Another thing to know is that these tables do not have a "primary key" defined in DB2. They only have "unique keys", which are what you see in the composite key definition below (see code).
T0026_AG_ELIG is the name of the parent table and the corresponding POCO class.
T0265_AG_IN_ELIG is the name of the child table and the corresponding POCO class.
Problem:
The problem is that when I execute the query, all the data is queried, the parent record is successfully mapped to the class, but the returned child rows do not map into the collection on the parent class. NHibernate does generate the queries for the parent and child data. When I execute my own query against the database, the correct data for the conditions does come back. For some reason, the child records are just not being bound to the property on the parent (T0026) class.
Question:
What do I need to do to get the multiple rows coming back from T0265_AG_IN_ELIG to map to their corresponding class and load properly into the specified collection property on the parent class (T0026_AG_ELIG)?
Collection Property of Parent (T0026_AG_ELIG):
Public Overridable Property IndividualEligibilityRecords As IList(Of T0265_AG_IN_ELIG)
Mapping Override for Parent (T0026_AG_ELIG):
mapping.CompositeId() _
[Code].....
(I've answered the question below with a hack. I'm fairly confident in it unless MS change the way that codedom serializers the designer code.)ETA2:I've worked out what is going on. I wondered why sometimes it would work and not others. It boils down to the name that I give to the internal property and the collection.If I rename the property 'Annoyance' to 'WTF', it will serialize correctly because 'WTF' is, alphabetically, after the name of the collection - 'InternalAnger'.It looks like the serializer is creating instances of objects alphabetically and needs my internal property to be created by the time it comes to create the collection.I can fix this with a rename, but that's a hack and I fear that writing a custom serializer is a big job - which I've never done before.ETA: Jesus, I'm sick of this. This problem was specifically about persisting an interface collection but now on further testing it doesn't work for a normal collection. Here's some even simpler code:
Public Class Anger
End Class
Public Class MyButton
[code].....
I have a user control with its own context menu, however I need to add additional items to that menu.
The approach I took was to have a dependency property called ContextMenuItems:
Public Shared ReadOnly ContextMenuItemsProperty As DependencyProperty = DependencyProperty.Register("ContextMenuItems", GetType(ObservableCollection(Of MenuItem)), GetType(SmartDataControl), New FrameworkPropertyMetadata(New
[Code].....
Is there a way to create a collection of collections? e.g. I created a collection ListOf(Lines) After I add all my lines to it, I want to store this colleciton in another listOf(Collections). The reason I want to do this is because i want to create several separate collections of lines and I'll need to loop through them all to look for a certain line and I thought this would be a good approach if it's possible.
[Code]...
I am trying to create a property which is as a class, which contains other certant properties you can edit, i.e:
Public Class exampleClass
Dim _var1 As String
Dim _var2 As Integer
[Code]....
Working on a project that tests up to 16 PC boards. The test routines are on a a backgroundworker thread. I want each PC board to perform the test routine on its own thread, so I would need up to 16 backgroundworkers.How do I go by doing this? Do I put 16 Backgroundworkers on the form? I tried to do it programmatically but I can't declare an array of backgroundworkers because withevents variables can't be typed as arrays. I guess I just need a kick in the right direction.
View 8 RepliesI have an issues creating Collections with Schedules, it creates the Collection, but it does not update membership as the schedule is blank [code]...
View 5 RepliesI have a collection of objects in vb.NET. Each object has two different IDs, lets call them ID1 and ID2.
I need to be able to quickly find a specific object in the collection based on one of these IDs. In some cases I have ID1 and in other cases I have ID2. I'm currently using the Collection data structure with ID1 as the key, but that doesn't help me when I need to find an object using ID2.
I'm writing a program that takes all files and directories on a computer and puts them in a collection, where I add a collection to the Collection for a directory with the key being the name of it and a string containing the Name for a file under the collections added I do the same,
[Code]...