Passing List (Of ChildClass) As Parameter To Method Expecting List (Of ParentClass)?
Apr 12, 2010
I have implemented inheritance for two parent classes called Table and Field. Each parent class has several child classes. In the Table parent class, I created a method that expects parameter List(Of Field).
I get an error when trying to pass in parameter List(Of ChildField) to the method that expects a parameter of List(Of Field). The error message is as below:
Value of type
'System.Collections.Generic.List(Of
com.hlb.icisbatch.data.ChildField)'
I'm trying to code a class of RandomNumber. One of the class methods needs to populate a "List (Of RandomNumber)" ... which was passed as a parameter to the method ... with 10 random numbers between 1 and 50. DEAD SIMPLE :)
I want to pass a comma delemited list of values as a parameter to a query I'm building using the designer in Visual Studio 2008 based on some strongly typed DAL tutorials I was going through. The query is going against a DB2 database. Here's what I want to do:
select * from prices where customer in(?)
It works fine win I pass in 123456 as ?But fails when I pass in '123456' (it is a char field so I don't know why this doesn't work; it must be adding these behind the scenes) or 123456, 123457 or '123456', '123457' I'm adding this page to a portal where all the data access is being done based on the DAL designer model with a BLL that calls it so I wanted to do it this way for consistency.
Public Class notifierMain Public Class Contacts Inherits List(Of row) Public Sub New()
[code]....
When I debug this winforms application I get curType = "notifier.notifierMain+Contacts+row" I want to the Validate function to know it is in MyContacts. How do I do this?
So for instance I have this method: LoadFunkyInfo(byval funkyData as string) And I pass it something like this:
LoadFunkyInfo(giantTable.Rows.Item(0).Item("blahName")). Should I do this instead?
dim foo as string = giantTable.Rows.Item(0).Item("blahName") LoadFunkyInfo(foo)
I read somewhere long ago, that it's better to assign the method to a variable and pass that variable to a method, as opposed to passing the method as a parameter. Is that still true? Or true at all?
What happened when parameter passing. Here is a test project I write. Public Class Form1 '1.test string Private Sub btnString_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnString.Click Dim str1 As String = "x" [Code] .....
From the project you can see, when pass integer type parameter (value type) into a method , if use ByVal keyword, the value won't change. If use ByRef keyword, the value will change (I can understand it, to my understanding, when using ByVal, It pass the value of the argument to the method; when using BvRef, it pass the address of the argument to the method, so the value can be rewrite)
Well, for the following two scenarios , I can't understand why. String type is reference type, but it acts like integer type. Val type is also reference type, but no matter what you use(ByVal or ByRef), the result will be the same. So my question is what actually passed into method? What's the underlying mechanism about pass parameter? What's the effect of ByRef and ByVal to value type and reference type?
Jst recently i came across the select() method of data table and felli n love with it instantaneously.
Basically I want query the data table on a date field, unfortunately the format of the date string returned from y database in to data-table and the date string i'm passing as inputs are different.
How can i make sure that the data is compared irrespective of the formats ? Can I use something like SqlParameters whoes data type is date for comparison ??
this is what i'm tying :
dim dat as date = "#1/3/2009#" dt.select("StzDate ='" & dat "'") entry in datateable dt : StzDate : 3/1/2009 12:00:000 Am I do'in something wrong ??
Also, can anyone redirect me to some site where I can learn a bit more about passing parameters to the select statement,etc...
I have a class which get all the bytes from a file, then it splits up the bytes into three parts (a header, index and body) these 3 parts get passed along to 3 classes (called header, body and index) respectively. When the bytes in the three classes gets modified how can I pass these changes back up to the first class (the one that got the bytes from a file). Must I have a property in each of the head, index and body classes called parentclass and then set the property when the classes are created? This could get chaotic when the 3 classes are split up further.
A file is loaded and the bytes put into a property called data() then the bytes are split at certian places/offsets into three parts. One part gets put into a property called data() in a class called header the other two part are also put into properties called data but in another two classes called body and index. The user, through the form ui, modifies the data in the 3 classes (header, index and body) I want this data to be passed back to the first class combined and then it can be saved as a file.
It looks like passing a list's enumerator to a function "byval" is quite different than passing it "byref". Essentially, regular "byval" passing will NOT change the caller's "enumerator.Current value", even if the function advances the enumerator. I was wondering if anyone knows why this is the case? Is an enumerator a primitive like an integer, without an object reference, and hence changes to it don't get reflected in the caller?This function is byval, and gets stuck in an infinite loop, spitting out "1" message boxes, because the enumerator's "current" never advances past 5.[code]The difference between the two functions is only whether the listFirstItem__ function accepts a byval or a byref enumerator.
Im having a hard time trying to pass the values from a list inside of a class. Im trying to display multiple lines of values from a list inside of a class. My "client" class stores multiple lines of values into a list(of class transaction), with the number value(num) counting each transaction that it adds to the list.
Code: Public Class Client Private m_tranlist As New List(Of transaction)[code]....
im trying to display each line that is stored in the list in a label, and im having major trouble. I know all of the results are added into the lists, but how do i call the list in my main form in order to display each line of all of the values? Would I have to look up an index or something?
I have been a VB user for quite a long time starting from dos-basic types. But only now I encountered with a quite a newb problem :) I tried to search MSDN for it for about a few days and at the end I have to ask this question here because I could not find anything about it.
From time to time I use functions or subs where one parameter is a word from a defined list.
E.g.
private function my_function(byval THE_PARAM as string) as ..........
where THE_PARAM could be "work", "home", "bus", etc. 5 words all together.
How can I define a function so that when I use it on the text of the program I had a hint not just like "THE_PARAM is a string", but I had a choice of those pre-defined words, so I could choose a word from that list.
What happens is that when the Item2 is selected in the first listbox, the second listbox automatically changes its selected item to the Item2. This happens just the same with the other listbox.
I have a function that returns a Datatable. I am passing a list of Integer as an argument. Then I thought tis would work.
Public Function GetEventsByEventType(ByVal EventType As List(Of Integer), ByVal DayInterval As Integer) As DataTable Using con As New MySqlConnection(strCon)
[Code]...
as you can see. I use string.join to convert the list of integer to something like this. '1,2,3'. Problem is that is read as a string so i get the incorrect results. I need to have where EventType IN(1,2,3).
I'm having difficulty passing a variables in a an array list. [Code] I have to pass the paramvals array to the function. The paramvals array contains the string but not the value of variable of that name. For example, parmaval(0) should contain the value of vSequence but it showing me that it contains string "vsequence".
Following is the format of the data stored in my arraylist.
A-Amsterdam B- Brussels C-Canada
so and so forth. I wan to search my array list by passing just the first few characters till '-' So if i have something like AA-Test then i want to pass just 'AA' to check if it exists or not.
I know that i can use contains or binarysearch but it does not serve my purpose as they both compare objects.
I have a class OrderManager, that takes a parameter of type LocalFuturesList on construction. Now.. It doesn't seem to matter if I use ByRef or ByVal here.. It still references the parent class instance of it. It also doesn't seem to matter if I type New or omit it.. Probably also because it's just an address reference. But why is it like this? And what type of objects "acts" in this way? Further I find that if I change the object in the parent class by deserializing from a file (with my method call shown), then suddenly this reference is broken in some way, so the OrderManager instance now holds Nothing I believe.If my observations are correct I see two challenges:
1. How to pass a list NOT by reference?
2. How to maintain a list reference through deserialization? [code]
I need help on passing checked list view items into one message box. my current code outputs multiple message box with the name of the item, depends on the number of items checked. what i need is to output into a message box all the items checked in my list view. the items should be posted in multiple lines. is there any way i can do it.
I am trying to get a methods name and add it to a list. I had a look around and came across actions. So far I have the following:
Protected Function MethodToString(method As Action) As String Return method.Method.Name End Function ... Me.Stages.Add(MethodToString(GetWeightFromSID()))
but it does not work when called as it says expression do not produce a value.
I would like to pull a set of records in a SQL sproc by passing in a list of system.guid and also by passing in a list of integer keys.I can put the guids ihto a string, of course, but the question is - how do I quote the test values so they are recognized as UIDs by SQLIn essence I was to DECLARE @pklist AS VARCHAR(1000)-- This would look like "'45F4AE2A-D27C-D711-83FD-0008C7FA9683','EC824D02-D37C-D711-83FD-0008C7FA9683','BA8E4D02-D37C-D711-83FD-0008C7FA9683'" coming out of the execsql from vb .net - I think :-) but it seems it needs to look likeSET @pklist = '45F4AE2A-D27C-D711-83FD-0008C7FA9683,EC824D02-D37C-D711-83FD-0008C7FA9683,BA8E4D02-D37C-D711-83FD-0008C7FA9683'SELECT * from dbo.members WHERE members.cpk IN (@pklist)This only returns the record matching the first UID in the string. Is there something I can wrap a t-sql VARCHAR string with so each guid will be seen distinctly?In trying to do this with a list of integer keys, the problem is the value is seen as part of a string and is not cast to an integerIt would seem creating a table from a parsed version of the string passed in and then doing a JOIN would accomplish what I need as well, but struggling with the T-SQL syntax for that.
I made an object that has several properties one of which is an integer.
I put all the objects into a list, and I wish to sort that list by the integer property, with the object with the highest property at item 0, with the object with the lowest property at the highest item # ( count -1).
I made the list of that item, as in
Dim GameList as new list(of clsGame)
And I wish to do something like the following
GameList.Score.Sort()
What is the syntax to do that? I looked up the MSDN and didn't really understand what it was trying to say
I have a data structure (which is a class) called user_class and I want to load all the users data from a database.Currently I have
While SQLreader.Read() Hold_user.username = SQLreader(0) Hold_user.BlahBlahBlah = SQLreader(1)
[code]....
Where return_value is a List of user_class and hold_user is an instance of the same class.
Dim return_value As New List(Of user_class) Dim Hold_user As New user_class
As the while statement loops through the read data, SQLreader(0),(1) and (2) are updated with new data, however they also appear to be updating the stored values held in return_value....
I am using the HtmlElement's InvokeMember function and was wondering if there is a nicely formatted list of all the strings that can be passed into that function.So far I know about these strings that can be passed into InvokeMember:Click, Focus provide a link to a list of all strings that can be passed into the InvokeMember function or write them down?
I have a query that can be summarised in SQL as follows;
Select S.StockCode From StockToCheck As S
[Code]....
Where the S var is a list of strings. This gives the error 'S' is not declared and points to the S in the function call / join (GetPOSStock). So it does not seem possible to do this in Linq, can anyone confirm?
I am creating a function and want to have IntelliSense pop down the list of valid options for a certain parameter in the same way that the MsgBox function behaves when you are typing your argument for which buttons you wish to include (such as MsgBoxStyle.OkCancel). I have done my best to search the internet but haven't found a thing which comes close to what I'm seeking. My monkeying around hasn't produced a satisfactory solution, yet, either.
A related additional thing, which I can live without but that would be nice to have, is the description of the current parameter, which appears below the function description as shown highlighted below MsgBox (Prompt As Object, [Buttons as Microsoft.Visual Basic.MsgBoxStyle = MsgBoxStyle .DefaultButton1], [Title as Object = Nothing]) AsMicrosoft.VisualBasic.MsgBoxResult
Buttons: Optional. Numeric expression that is the sum of values specifying the number and type of buttons to display, the icon style to user, the identity of the default button, and the modality of the message box. If you omit Buttons, the default is zero. This is my first post. I'm relatively new to VB .Net.
I've got a simple function that takes a List parameter. While working with it, it copies it and reverses the copy using .NET's List(Of T).Reverse method.
I have a class myClass. MyClass has a property myName. I have a generic list myList(of myClass). I have to check if value of myName in all myClass objects in myList is same and is equal to a string myString. I have created a method:
Private Function IsMatching(ByVal objMyClass As MyClass, ByVal strMyString As String) As Boolean If objMyClass.MyName = strMyString Then Return True Else Return False End If End Function Now I want to use is TrueForAll method of Generic list. How can I use it ?
If there was No second Parameter in IsMatching method, I could have simply used myList.TrueForAll(AddressOf IsMatching) But since there is a parameter strMyString, I dont understand how can I use IsTrueForAll method. How can I use IsTrueForAll method in this scenario.
