C# Accessing Properties Of An Object From A Collection Class?
Jun 10, 2009
I am moving from VB to C#. I am trying to loop through a collection class which is a collection of data classes but I can't seem to get the actual values out of the data class properties(find the correct code to do so). I have a method that loops through the collection class(Contacts) and saves each record(Contact). I am using reflection because my method will not know if it is Contacts class or a Customer class and so forth. Here is my code in VB(watered down)
Public Function SaveCollection(ByVal objCollection as Object, ByVal TableName as string, ByVal spSave as string)
Dim objClass as Object
[Code]....
The C# code keeps returning null. In my locals window I can see the proprties on the class on objClass and the value of the propery but I can seem to figure out how to access it through code. I used the DictionaryBase because that seems to closely match would I need to do. My data class(Contact) has a bunch or properties that match the field names in the database of the Contact Table. After I get the propInfo variable set I then set up my SQLParameter with the fieldname, datatype etc and then set the value to the propInfo.value.
Is it possible for one class to access an array of values within another class as a readonly property of the second class? All of the examples and references on class properties imply that one can only retrieve one value by calling a class' property.
I am somewhat new to object oriented programming and am attempting to flatten a Linq object hierarchy by using a shim class.how to initalize a derived class with property values from a base class?I have two objects, a base object with about 100 properties, and a derived object which inherits from the base object and adds a few additional properties beyond those of the base object. My simple constructor creates the derived object, but I am looking for a way to initialize the derived object properties with values from the base object.Right now I am using reflection to iterate over the properties individually and I suspect there may be a better way. The following example shows my shim class constructor for the derived class, and two properties:
newProperty1 - a new string property of the derived class
flattenedProperty2 - a new string property of the derived class, copied from a 2nd-level object of the base class
Code example:
Public Class derivedObj Inherits baseObj Private _newProperty1 As String[code].......
Is this the correct constructor approach to flatten the object hierarchy using a shim class? My second question relates to initialization of properties in the derived class. The constructor above creates the derived object, but what is the best way to initialize the derived object properties with values from the base object? The following code uses reflection to iterate over the properties individually, but I suspect there may be a better way.
Code example:
' property names are in the string array fieldNames
'baseObjQuery is an ienumerable of baseObj
'derivedObjList is a list of derivedObj[code].....
Is there a simple way to initialize values for the properties in the derived object based upon the values of the common properties in the base object?
I have to make a VB project for one of my college Co-Sci classes. However, I am having issues doing what I think is logically possible. Part of our project entails creating a user defined class, then create a form that then instantiates an instance of the object type. After that we are to list the item in a listbox. That is all well and good and works fine.
What I need help with is looping through each object in the listbox, getting some data from the object, then moving to the next.
I have been trying something similar to c++. For example, an object contained in a c++ array can be accessed like this:
array[index].someObjectMethod().
How would someone do something similar to that for objects contained in a VB listbox? I imagine it starts something like this:
I have a class which extends HashSet(Of T).I am trying to evaluate some custom properties of this HashSet during execution and make decisions based on those values.
During debugging, I am pausing execution and adding a Watch on my instance of this HashSet.
The Watch only provides me with a view of the Count of the HashSet and the objects contained by the HashSet.How can I get the Watch to show me the other properties of the HashSet?
I have a class in which some of the fields are also classes.
I can put values in the "normal" properties, but in the others when o try to assign values it gives the: "Object reference not set to an instance of an object"
But the code compiles fine.
dados_Defenicao = New ServiceReference1.draftClaimEntryDefinition dados_Defenicao.arCode = "123" dados_Defenicao.claimMarket.warrantyType = "w" - Here it gives the error
I have a property grid and I want to be able to set the selectedobject to a class. The class contains properties. This is what I have, but it 'OtherFiles' is not an object.
pgProperties.SelectedObject(OtherFiles)
How do you create a class as an object. In VB.NET 2008 please. C# is ok.
currently in my application I have a Global Collection that is a Collection of Collections.Currently I am trying to add items/ elements to one of the child collections of the Global Collection but I am unable to use the collections methods of the child.When I assign a variable to the child collection and return the collection it is just an object with the collection inside.
Ex: Dim GlobalCollection as New Collection Dim ChildCollection1 as New Collection Dim tempCurrentCollection[code]......
how to implement UI, BL and DAL in a project the way that I see it as a requirement for some projects. The way I am able to do a project now is from a form create an object of a class in which there are properties and functions that do database selects, updates and deletes. Looks to me that doing a project like that is separating the UI from the DAL. In an update button click event I may call Obj. Delete (txtCustID.txt) for example. I don't understand the part of further breaking it down to include a Business layer; in which a vb solution is made up of three solutions.What goes in the BL?Does the BL call the DAL?
I'm trying to support Basic.NET on my framework so I'm trying to convert C# 4 code to Basic.NET 10. Microsoft is committed to "co-evolve" these two but I'm having a problem with collection initialization... I found that I can initialize a collection much like in C#:
I have an exceptionhandler function that basically just writes a line to a textbox on Form1. This works fine when being run normally but the second I use a thread to start a process it cannot access the property. No exception is thrown but no text is written to the textbox:
Public Sub ExceptionHandler(ByVal Description As String, Optional ByVal Message As String = Nothing) ' Add Error To Textbox If Message = Nothing Then Form1.txtErrLog.Text += Description & vbCrLf Log_Error(Description) [Code] .....
Is it possible to access a form's properties from a thread this way or would it be easier to write to a text file or similar and refresh the textbox properties every 10 seconds or so (Don't see this as a good option but if it's the only way it will have to do!).
If I have a custom windows service running on a server, is there anyway I can access the value of a property/variable within that service? For example, I would like to have a client vb program be able to "read" the value some variable from that service. A simple example would be the service would capture a boolean value of the success or failure of the last time it kicked off a process. I would then like to have a client windows app "connect" with the service and be able to read that boolean value.
I want to know the correct way to access an object that is stored as an object in another object...phew. Here is what I'm trying to do...
I'm creating a restaurant map and to keep things simple I have 3 classes -- cServer, cTable and cGuest. cTable has a property which should contain a cServer object eg
Public Property Server() As Object 'Called when the property is read Get
I'm trying to update a dependancy property in VB.Net 4.0 inside of an Async callback. I feel like I am doing this correctly but I'm still getting the "The calling thread cannot access this object because a different thread owns it." error. Does someone see a better way of using delegates in VB.Net 4.0?
Private WithEvents myObj as CallingObject Private Delegate Sub MyErrorDel(ByVal strError as string) Public Property ErrorMessage As String
[code]....
Whenever ErrorMessage gets set inside of DisplayError an exception gets thrown, even though I am using the dispatcher to call DisplayError.
I am trying to access MS/Word document properties without opening the file in Word. Right now I have an app that reads the document properties but it has to open the document in word. This makes it run very slowly and also makes it susceptible to crashing if the document is corrupted. In Windows Explorer, you can right-click on a word document file and select properties. The ensuing dialog box contains, in addition to the usual information, two additional tabs labelled "Summary" and "Custom" that correspond to the same tabs in the dialog box you can open from File/Properties menu in Word. I know windows explorer is not opening the document in word because there is no instance of word.exe in task manager and because it has no difficulty in obtaining this information from the file even when it cannot be opened in Word because the document has become corrupted.If anyone could help me figure out how to read custom and built-in document fields (properties) from the file without opening it in Word,
I have a class that has the following property that is generated by the methods in the constructor.
Public Class clsLoadTables Private _ds As New DataSet Public Property ds() As DataSet Get
[CODE]........................
My problem is that I do not want to inherit this class, but I have other classes that need to access the ds DataSet property. If at all possible I would like to not use inheritance and not load my datatable more than once in the program.
Here is my failed attempt to access the property inside another class that is not inheriting clsLoadTables:
[CODE].........................
How I can access this dataset that I want to load only once in the program from many classes without using class inheritance or a global module?
I have the following defined in my "Form1":So that I can access all my database functions anywhere in the main form (database connection is initialized via the "private sub new()" function in the DatabaseManager class.The works fine for all queries done in form1, however I have many other classes I'd like to be able to access the database from.Does anyone know how to access the initiated class in my example? Since right now it is initiated in the main form, if I try to access any functions inside any ot
I need to migrate from Excel 2003 VBA to Excel 2007 VBA. When Microsoft introduced Excel 2007 it removed many objects from the previous versions and added some new objects. Also it hid some properties of particular objects. These hidden properties can be viewed by going to the object browser, right clicking any object and selecting "Show Hidden Members". My problem is I need to access these hidden properties. Is there any way I can access these properties. I can successfully migrate from Excel 2003 VBa to Excel 2007 VBA with the same functionality?
I have used the following code to generate buttons dynamically. I want to know how to code in such a way that if i click one button, there should be some change done to some other button in the same form. Since all the buttons are generated in the loop, i do not know how to call one button elsewhere in the code.
Private Sub random2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Dim i As Integer
how to handle movement of buttons that are made in runtime. What my program does is writes the name of a button that is made in runtime, the left, and top cordinate into a textfile. When the user reopens the program it needs to load the button in the same spot. So far i have a streamreader reading the file in each line. There is a one sentence split by ",". Each of the three components are loaded into an array. how can i call the buttons it i am unsure of the name. Possible answer could include using sender, addhandler.
Private Sub LoadBuildingToolStripMenuItem1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles LoadBuildingToolStripMenuItem1.Click Dim File As OpenFileDialog = New OpenFileDialog
I'm writing a really simple file updater which downloads files off from a website and saves them. The download routine is working well, except that it freezes the project while attempting to connect to the host. Easily solved with threading except now when I try to access other form items such as text boxes, labels, form caption, it says I am not doing it in a safe manner and prompts an interrupt in debug. I did some reading on it and I'm still not sure what to do, I'm very new to vbnet and it is still a little confusing to me.
Error: Cross-thread operation not valid: Control 'Form1' accessed from a thread other than the thread it was created on. Imports System.Threading Imports System.Net Imports System.IO
I'm looking for a tutorial on how to Adding a list(of Class) or Collection as another Class's Property.What I am after is something like the Columns Collection for the DatagridView control.I would like to add Items in the graphics screen. Where the item list is displayed in the left panel and the selected Item properties are displayed in the right panel.
I want to build a MVC helper function for which I pass a Entity Framework object and have it build a select. Generally speaking I tried something like this:
Public Function RenderSelect(ByVal helper As HtmlHelper, ByVal sSelectName As String, ByVal aItmes As Array, Optional ByVal sTitleKeyName As String = "name", Optional ByVal sValueKeyName As String = "id") As String ' open select
[Code].....
However, it isn't working. It would be great to have a way to do this and pass the current entity object.
