.net - Declare An Optional ArrayList With Elements Inside?
Nov 19, 2010I ve an interface like
[Code]....
but I want to declare an optional arraylist with default values... how to do that?
I ve an interface like
[Code]....
but I want to declare an optional arraylist with default values... how to do that?
I can create an ArrayList, but, is it possible to create it WITH some elements already?Normally, your arrays are empty, but what if I want to create an array with a few elements already?
View 2 Replieshow do i clear all elements in an arraylist?
View 2 RepliesHow could I declare an arraylist as strong typed arraylist of Strings I have tried this code
Dim newAr As ArrayList(Of String)
I 've an ArrayList and to join all its elements with a separator in one string I m using...
Dim s As String = String.Join(",", TryCast(myArrayList.ToArray(GetType(String)), String()))
however, I would know if there is a smarter/shorter method to get the same result,or same code that looks better...
i have created an array list and added value using
arraylist.add(value)
now i want to sum all the value inside the arraylist.
Dim sublist As New ArrayList()
sublist.Add(1)
sublist.Add(0)
sublist.Add(0)
[code]....
how can get the sum of those added value.
driving me nuts...been googling my fingers off but i can't seem to find the solution to getting the "id" of an elemnt that is inside of an iframe and setting a value to the element.
[Code]...
I've got 2 DataTemplates defined for a Listbox Control. 1 Template is for the UnSelected State and the other one is for the Selected State(showing more detail than the UnSelected State).[url]...
about how to access the Elements inside the DataTemplates from Code behind.
I get it right, but it only finds and returns an element of the UnSelected DataTemplate. But when i search for an element in the Selected DataTemplate i get a NullReferenceException.
I have a Visual Basic .Net 2.0 program. I'm moving the settings from an older settings file, to an app.config program settings file. I'm trying to do this as nicely as possible.
So, I added my setting as shown in this image.
On load I do this:
If My.Settings.databaseConnectionSettings Is Nothing Then
My.Settings.databaseConnectionSettings = New ArrayList()
End If
[Code]....
So, the question is, how do I get that arraylist of my DatabaseConnectionSettings saved to persistent storage? I want to do this in the cleanest way possible. That is, I don't want to have to convert it to a string or save it to a separate file every-time I want to use it. I would like to be able to use the My.Settings accessor method.
I am teaching myself VB, and when I try to run this program, I am getting "An error occurred creating the form. See Exception.InnerException for details. The error is: Object reference not set to an instance of an object." If I was to declare the variables inside each event handler, the program runs, but why won't it run when I make the scope public? Seems repititous having to declare the variables in every event handler. [code]
View 7 RepliesCreate a class named Service. Inside the Service class, declare a class variable named Started. The datatype of this variable is Boolean.Public Class Service Dim started as Boolean End Class Create a class named Server. Inside the Server class, declare a dynamic array that can contain elements of the type Service.(Note: For convenience, both the array and the variable Started can be accessible from a client program that creates an instance of Server and Service respectively)
Create a constructor for the Service class. When the constructor is executed, it will set the value of the class variable Started to True. Create two new classes: WebServer and DatabaseEngine. Both of these classes inherit from the class Service. Inside the Service class, declare a Sub procedure (method) named Terminate. This method should display the following text Service stopping in a message box when executed.This method can be overridden in classes that inherit from Service class.
Inside both the WebServer and DatabaseEngine class, override the method Terminate inherited from their base class Service. Both methods should first call the base class Terminate method. The messages Web server stopping and Database engine stopping should also be displayed in a message box when the Terminate method for the WebServer and DatabaseEngine are called respectively. These messages should only be displayed if the Started variable inherited from their base class is not equal to False.
Inside the Server class, declare a method named Shutdown. This method does not return any value. When executed, it will call the Terminate method for each of the Service instances (if any) in the arrServices
array. You should call the Terminate method within a For Each loop that loops through the elements of the arrServices array.
In the Sub Main method, create an instance of the class Server. Set the size of the arrServices array in
your Server instance to contain 2 elements. Create first a WebServer instance and then a DatabaseEngine
instance into this array. Call the Shutdown method from your Server instance.
I am trying to have an optional Date value in one of my sub but since you cant set Date to nothing, this doesn't work. And i cant set it to the Date.minvalue inline.
Private Sub abc (ByVal A As String, Optional ByVal B As Date = Nothing)
End Sub
So, i went and set it to some date in the past.
Private Sub abc (ByVal A As String, Optional ByVal B As Date = #1/1/2001#)
End Sub
what would be the proper way to handle the default value for an optional Date?
What I am doing is iterating through all the groups that belong to the top group (Generic reports). Then I take advantage of the GroupPrincipal.GetMembers(True) which will recurse through a given group name. I test to see if the user exits under that group and if true I put the group name in an arraylist.
I use the for each principal in GroupPrincipal.GetMembers to loop through each returned user to see if they exist.
Is there a way to put all the returned users Principal.Name from a given group in GroupPrincipal.GetMembers into an ArrayList? This would allow me to to use Arraylist1.IndexOf to search for user. Which would be much faster then iterating through a returned list using the for each construct.
Sub RetAllMbrs(strUser As String)
Dim oPC As PrincipalContext = GetPrincipalContext() '<- this is function somewhere else in the code
[Code].....
I have a problem in Treading.I have a code like this;[code].....
I want to change ListBox1 with ArrayList. But I couldn't find how to use adding a string to ArrayList in tread.
I created a method and pass the element type, id, and any inner text that instantiates a new html element. The last statement: Me.Controls.Add(element) adds it to the end of the page, but I would like it to be inserted in a specific position (between 2 divs within a form). What I am describing is very similar to this post on SO here, although it was for javascript.
View 1 RepliesI have an arraylist (arrFirstArry) which I use to populate another arraylist (arrNoDuplicates) preventing any duplicates from being added. This works fine. What I would also like my code to do is prevent adding any partial values which may exist from being added. i.e. my array is like this
[Code]...
I have two structures Public Structure myResearchData
Public batchName As String
Public arraylistRData As ArrayList
End Structure
Public Structure myResearchSubData
Public researchDescription As String
[Code]...
Cleared MyResearchData.arraylistRData for new data to be put in but it also clears the arraylist inside MyResearchDataAList and didn't old the contents of the arraylist
What I need to do is read an ArrayList in My.Settings and add another ArrayList to it. The first think I'm trying to do is load My.Settings.Records into myArrayList. I'm not quite sure on the proper way to do this. I've tried things such as Dim myArrayList As ArrayList = My.Settings.Records, I'm not sure if I need New and I'm not sure if I need .Clone or .CopyTo.
Then I have another ArrayList myArrayList2. To get this into myArrayList I've done: [Code] Then to save it back to My.Settings I've done. My.Settings.Records = myArrayList. The problem is I keep on getting Object reference not set to an instance of an object error on the AddRange line. My.Settings.Records is definitely an ArrayList and it will sometimes = Nothing. The objects will only ever be strings.
Dim Document = XDocument.Load(FileName)
Dim findElement = Document.Elements("GradeProfile")
[code]....
I want to create an array of an array (or arraylist of an arraylist) to hold strings.I want to fill an array1 with string values Then add this array to array2. - but only taking up 1 row in array2 e.g something like array2(index)=array1 Then clear array1 then loop through this again with different data, and add it to the array2.so will end up with something like
array2(0)... contains a collection of array1 data
array2(1)... contains a collection of different array1 data
.. and so on
i think i need to make new instances of array1 each loop, but not sure.I dont mind if it uses arrays, or arraylists, or lists, or structure of arrayslists?
s there a difference between the arraylist in visual basic and arraylist in C#? I had to convert some C# code to VB and there is a call I make in a third party api that requires me to pass in an arraylist. When I do this in C# it works just fine, but when I do this in VB, I just get back a vaque exception from the api.
[Code]...
The exception I get is very vague and comes from the API. All i get is, "ARException Occured".
I'm trying to convert come vb.net code into C# from another programmers old work but came across optional in one of the functions.[code]...
It seems like instead of using overloading, VB.Net has an option to create it into one method/function. Does C# have a similar equilvalent or do I have to create a method for each possbility?
I have a third party dll that contain a class, SampleClass1
Public Class SampleClass1
Public SomeValue As Double
Public Function Test() As Double
[code]....
My intention is if the dll is found, use it. Else ignore it. However, if the dll is not found, the program throw an Invalid OperationException.
I have an application that does a search of our database (exposed via EF) for records meeting certain conditions. We have two main tables (Jobs and Recipients). Recipients are linked to the Jobs table by a Job ID.The job record has various fields (Process Date, NameJobType). The recipient has a lot of Name and ID fields (e.g. Account Number, Surname, etc)
View 1 RepliesI currently have this XML schema :
<PSC5>
<POI_ORI>
<CIT>LIM</CIT>
</POI_ORI>
</PSC5>
if user want to add a new option, the final schema will be :
[Code]...
I'm looking at an old module to add some new features. I noticed this in a subroutine declaration:sub foo(...,optional fum as integer = 0)the later if not isnothing(fum) then <do something>I'm wondering, will <do something> ever be executed? I'm guessing not, since fum has a default value, but I want to be sure I'm getting this correctly.
View 12 RepliesIt says that I can't have structures as optional arguments.That's really annoying for my program. Isn't there any way to circumvent this?
Sub fa(Optional ByVal colz As System.Drawing.Color = Color.AliceBlue)
End Sub
This example cannot compile
I have an application that does a search of our database (exposed via EF) for records meeting certain conditions. We have two main tables (Jobs and Recipients). Recipients are linked to the Jobs table by a Job ID.The job record has various fields (Process Date, Name, JobType). The recipient has a lot of Name and ID fields (e.g. Account Number, Surname, etc)I want to present a search screen where they see a list of fields to search on. The ASP.net code then sees which textboxes the user typed in (or selected), and builds a query based on that. [code] Where I'm stuck is figuring out how to add in additional where clauses. Should I just use Entity SQL?Can this return strongly typed EF objects as well? And is it possible to return both the Jobs and Recipients objects?
View 1 RepliesI have a method written in VB.NET. It looks like this:
Shared Sub SomeMethod(ByVal Id As Guid,
Optional ByVal str1 As String = "foo",
Optional ByVal str2 As String = "")
I want to call this method from C# 3.0 and I want it to use its default arguments. I tried passing System.Reflection.Missing.Value, but I cannot cast it as String. Is there any way to do that?
However, I am wondering if there are any workarounds or plans for incorporating this feature into VB.NET in the future?What I'd like to do:
Public Delegate Function Deserializer(Of T)(ByRef Buffer() As Byte, optional ByRef BufferPosition As Integer = 0) As T
'Implementation of a func that matches the delegate'
Class A
Public Function Deserialize(Byref Buffer() as Byte, optional Byref BufferPosition as integer = 0)
....
In the absence of specifying "optional" inside the actual delegate itself, it'd at least be nice to be able to do it in the function implementation only:
Public Delegate Function Deserializer(Of T)(ByRef Buffer() As Byte, ByRef BufferPosition As Integer) As T
'Implementation of a func that matches the delegate'
Class A
Public Function Deserialize(Byref Buffer() as Byte, optional Byref BufferPosition as integer = 0)
....
At least this second way, the functions for the delegate will always have a value mapped to each parameter, although some may come from the function side and not the calling side.