Why won't XMLSerializer process my generic list?
Sub Main()
Serializing()
End Sub
[Code]....
I get an exception on the "Dim ser" line, saying "Testing.Module1 is inaccessible due to its protection level. Only public types can be processed." ("Testing is the name of the application, and "Module1" is the name of the module; this is a console application).
I have a custom class that has one property as a collection.For some reason XmlSerializer doesnt like the class having a collection property and the Serialize Fails!If I remove the collection property it works! Is there a special way of getting the collection in the class to work?
View 1 RepliesI have an xml file with elements that look like this (abbreviated for clarity):
<post id="1" tags="tag1 tag2 tag3 tag4" />
I want to map this to the following class using Xml Deserialization, but I can't find a way to map the tags attribute to an actual List(Of String).
<Serializable()> _
<XmlRootAttribute("post")> _
Public Class Post
[Code]....
Is there any way to override the default Deserialization?
I have a Generic.List(Of ImportedVehicle) - ImportedVehicle being a simple class as below.There is an enum property which is marked as public.When I serialize to XML using an XMLSerializer, the enum's value is just set to it's default value (which is NotAllocated) and doesn't actually represent the value that is set in code.[code]
View 1 RepliesI am trying to use a Web Service to return Json for a Collection of Users from a Database Table. I'm only new to .NET (< 1 week experience), and I don't want to use the UpdatePanel for AJAX. I have tried using the JavaScriptSerializer as well as Json.NET to serialize. Both cases seem to spawn an Infinite Loop.[code]
View 1 RepliesIm working on my first n-tier application. I am trying to serialize a structure and Im getting an error"Soap Serializer does not support serializing Generic Types : System.Nullable`1[System.DateTime]."Here is the structure that is being serialized
Namespace Structures
<Serializable()> _
Public Structure structAllergy
Public AllergyID As String
Public ProfileID As String
[code]....
The bold line is the line that is throwing the error.
I have the below code and it works fine, it's this way because I need to manually calculate some data before adding it to the Listview control.
Code:
Dim mList As List(Of ListViewItem) = mDataBase.GetRecords(LvwChecks, "CheckGroups", <Query>, GetType(CheckItem))
If mList.Count > 0 Then
[Code].....
I know its generally a big No-No to modify a collection that you are iterating through but unfortunately i didn't design the code that i'm trying to modify. All over the place the following is done:
for each log in Logs
logs.Delete(log.LogId)
Next
Delete pretty much just deletes the log from the database and removes it from the collection. Previously the Logs object was using a Non-Generic collection. I changed it to use a Collection(Of Log) so i can LINQify the object. Now every time i call next/.MoveNext is called after the first delete the following error happens:
InvalidOperationException:"Collection was modified; enumeration operation may not execute."
I understand why i'm getting the error but i don't understand why it never happened with the Non-Generic version. Is there anyway to get around this error? There really is no way i can take the time to change every place where the delete logs like this (codebase is large). Id like to just remove the code in the Delete function where it removes it from the current collection because i'm assuming no code does anything with the collection after its done but you know what happens when you assume.
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?
Ok say I have this Dim MyQueueOfClients as new Queue (Of TcpClient) I also have two threads.
In thread one a TcpListener waits for connections then adds a connected TcpClient to MyQueueOfClients.
MyQueueOfClients.Enqueue (TcpClient)In thread two I then check to see if there are any Clients in MyQueueOfClients. If so I then remove them from the MyQueueOfClients.
MyTcpClient = MyQueueOfClients.Dequeue I think the question Im asking is this thread safe?
Can I Enqueue and Dequeue at the same time from different threads?
Well it helps if you read everything. I have just read this as well
A Queue(Of T) can support multiple readers concurrently, as long as the collection is not modified. Even so, enumerating through a collection is intrinsically not a thread-safe procedure. To guarantee thread safety during enumeration, you can lock the collection during the entire enumeration. To allow the collection to be accessed by multiple threads for reading and writing, you must implement your own synchronization.
Say a collection grow. Once it's size reach 10k, I want to get rid the first 9k. How to do so?Oh ya I could use removeRange.Is there another function that will output say, the last 1k of the element, say if I do not want to remove anything? Something like tail or something.
View 7 RepliesI wrote a class which imports System.Collections.ObjectModel. For the management of the collection, I've written:
Default Public ReadOnly Property Item(ByVal vntIndexKey As Integer) As ItemType
Get
Return CType(mCol.Item(vntIndexKey), ItemType)
[code].....
To the point: I need to transfer a custom object's event through a generic collection object containing these items so that any class using the collection can see that changes were made to one of the items in the collection.
I.E. An item event that triggers a collection event
[Code].....
Due to the application requirements, I need the Collection and Items to send immediate notice of various changes that occur to the Collection Class and its items. I've already got my events set-up regarding for the Collection Class, but I'm struggling with coming up with a workable solution for raising events for the items.
I've got an event for the DeviceLayer item set-up, but how do you transfer that event through the CollectionClass so that any other class using it will see that there was a change to one of the items in the collection?
This is really a continuation from my earlier post. I've never worked with this datatype/collection (system.collection.generic.Ienumerable) before so I'm struggling to declare the query globally so I can reference the results within other sub routines/functions. I also am struggling to convert it to other types.how I can convert the collection of xml elements/system.collection.generic.Ienumerable into an xmltextreader (I know I will have to change the query below as it select the value of the node and not the node itself) I imagine by converting the query result to system.IO.stream My first port of call was MSDN but I find the material very difficult to understand for this particular subject.
[Code]...
I 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?
There are a lot of different generic collections available, so the wisdom in creating a new one may be questionable right from the start.However, I often find myself wanting the same features from my custom generic lists, but cannot quite find all of those features in an existing object; namely, I would like to have a generic collection which works like a List or Dictionary (much like the System.Collections. ObjectModel. Keyed Collection(Of TKey, TValue)), but also works like a BindingSource does when it is bound to an ADO object (that is, it supports full sorting and filtering as well as currency).A feature I almost never need however, is transactional adds (the BindingSource's ability to 'cancel add-new').Again, with so many existing collections out there, I should take a moment to go over the reasons why none of them quite meet my needs.There is the System. ComponentModel. BindingList(Of T) which would provide some of the functionality of a BindingSource, but has strict requirements about the type {T} implementing IComparable in order to support sorting, and does not provide filtering (it is not an IBindingListView).It also only maintains a base item list by index, so does not provide keyed access.We could use simple databinding with a custom list inheriting from System.Collections. ObjectModel. Keyed Collection(Of TKey, TValue) bound to a BindingSource, but again TValue would have to implement IComparable to support sorting and we would still not have filter support.So to get all the features I was after, I decided that the best thing would be to create a new generic collection object which implemented IList, IDictionary, IBindingList, and IBindingListView (along with a few others) and would be capable of serving as a simple list, or as a binding source while providing full sorting and filtering over any newable object type.
To that end, I've created the KeyedObjectModel which contains the KeyedBindingList(Of TKey, T) generic collection/binding source. This collection can be used as a typical list, or as a binding source (you do not need an additional BindingSource component between the collection and UI controls, although you could certainly have one).Various constructors are provided in order to initialize an instance of the collection as either an enhanced list-dictionary, or as a complete BindingSource.Any object that has a public constructor which takes no arguments can be used at type {T}, providing that the object has a property of type {TKey} which will contain unique values for each entity in a given collection.If the object implements System.ComponentModel.NotifyPropertyChanged then the collection will also bubble up property changes on the current item to the collection's CurrentItemChanged event.An implementation of IComparable on type {T} is irrelevant because sorting and filtering are performed on the property values of {T} based on the type of the specified property.The current design of KeyedBindingList(Of TKey, T) is in an 'alpha' stage.The class is mostly complete from a feature implementation standpoint, however, the code has not yet been optimized and the base collections of values, keys, and view are being maintianed in generic lists of their own, rather than raw arrays.However, even without performance tuning, the collection appears to be performing quite well, up to a few thousand entries, given the amount of flexibility and funcitonality it provides.At this stage, I would really love to get some peers to try using the compiled DLL and beat up the collection a bit.Once the code has been proven and optimized, I will publish it as an example.It is a fairly complex class though (currently made up of eleven or so partial classes) so I don't really want to post the code until it has been optimized. [code]
I am having problems with serializing and de serializing my objects.The following is my code for serializing buttons and labels which I have in my form.
Dim nodes As New List(Of nodeclass)
Dim objStreamWriter As New StreamWriter(filelocation)
For Each btn As Button In myNodeBtns
Dim u As New nodeclass
[code].....
I get an error: There is an error in XML document (20, 3).Now I have found out that this is because I have 2 root elements and 2 xml declerations. When I save the xml for the button and te xml for the label in 2 different files, I have no problem. However I have no idea how to go about saving the xml for both of them in the same file and deserializing it back.
We have migrated our Vb6 application to VB.NET using a third party tool. Now we are in a process of Refactoring and introducing object oriented concepts in the application.
In VB6, we were using structures in many places. As a part of introducing object oriented programming,
1. is it a good idea of changing all Structures to Classes? or Is there a concept of "Generic Structure" similar to Generic collections, Generic classes?
2. Can some one guide me any source containing guide lines or best practices for applications that are migrated to VB.NET from VB6 and implementing object oriented programmaing.
I have not yet tested this..but before I do that, I am just wondering, let's say you have a byte stream, and you want to deserialize that into an object?[code]...
View 3 RepliesI am using the XMLSerializer to create an XML Schema. In one part of the XML, I have an element called 'parameters', which returns a collection of strings. The output is supposed to look like this:
[Code]...
0I Have a vb6 application that uses .net objects via COM. When one of this objects calls code which instantiates XmlSerializer vb6 aplication crashes.Just this line fails: Dim x as new XmlSerializer(GetType(CustomClass))I agregate that these objects load assemblies dinamically but only it crashes over vb6 aplication. In .net 100% aplication this not happens.
View 2 RepliesI'm trying to serialize a user's preferences by means of an XMLSerializer. The preferences class contains Strings, Integers, Booleans and several Color structure variables. The serialization doesn't throw any errors, however the generated xml file has empty values only for the color variables.I tried the following two declarations of the XMLSerializer object, neither workerd.
[Code]...
I've been having problems with following code on some computers, while it's worked super on others (most):
Dim xmlSer As New System.Xml.Serialization.XmlSerializer(GetType(XMLContext))
which produces the stacktrace:
System.ArgumentNullException: Value cannot be null.
Parameter name: type
at System.Xml.Serialization.XmlSerializer..ctor(Type type, String defaultNamespace)
How can that code throw that exception, when the argument is drawn from a gettype call, and note that it doesn't happen when debugging on my own PC, only when it's installed on some of the client PC's???
I am trying to deserialize an Xml file content into a specific object. Everything runs fine but when I include empty tag of type date or time in my xml(having xsd that describes my xml structure) the deserialization fails. What can I do to make deserialization working when empty date tags are appear?
View 1 RepliesIs there any way to create an XmlSerializer that stores along with the serialized data the data type, then when deserializing, it automatically identifies the type of the serialized object and creates an object of that type (returned as object).
View 1 RepliesI have the following class which I want to serialize to XML:
[Code]...
Consider:
Public MustInherit Class Column
Public ReadOnly Property ReturnSomethingUseful() As Object
Get
'return something useful
[code]....
But this gives the following error:
Public Overrides Function ParseValue(sValue As String) As Boolean'
cannot override 'Public Overridable Function ParseValue(sValue As String) As Object'
because they differ by their return types.
I accept that you can't do this, but I'd like to be able to preserve the semantics of what I'm. trying to do, which is to have an untyped version that deals with Object, but a typed version in derived classes that knows about the specific type T.
I wish to put the XMLSerializer behind a 'facade' class of mine so that user wont have to supply type info to the constructor. But doing this has a problem. Consider this class:
Class XmlFormatter
Private Shared xs As XmlSerializer
Public Function Deserialize(ByVal serializationStream As Stream) As Object
Dim o As Object = Nothing
[code]....
The problem is that the user of this class cannot use Deserialize without first using Serialize because the XMLSerializer instance is created in Serialize and it is shared. But using Deserialize without this instance will simply return Nothing.
I have a Journal that records entries for different types: Journal(Of ParentT)
[Code]....
I am trying to construct a generic interface class with generic functions. My goal was to use this to implement multiple worker classes for database interaction that have the same basic functionality. Each class will deal with different object for example, category, product or supplier but unless the the functions in the interface are generic that this won't work.This is the interface code that I have but I don't know if I have done it correctly. [code]
View 2 Replies