I'm making a function that searchs an array of Customers and returns a Customer object by a given ID.
I'm trying to do so with Lambda Expressions,and this is what I have so far:
Public Shared Function FindCustomer(ByVal ID As Integer) As cCustomer
Dim customer as New cCustomer = _ _
Array.Find(arrCustomers, Function(c as cCustomer) c.ID = ID)
Return customer
End Function
[Code]...
I'm using Streamwriter/Streamreader for the first time in this project and keep getting an "Argument out of Range Exception was unhandled" error.It says "length cannot be less than zero. Parameter name: length."This happens at "dblYearly Income." Also, how do I find out the number of occurrences of an item in an array? For instance, I have a Race combobox and need to find out how many occurrences there are for each race.Also, is there a way to count the number of occurrences of an array itself, I guess the upper index value? [code]
View 7 RepliesI have an array called linedistancearray.I am now trying to find the smallest integer in that array and store it another variable called mindistance..The following is my initial idea: I sort the array and then pick the integer with index 0. Array.Sort(linedistancearray)However what I get is the first item being a 0 not the smallest integer value in the array I need. HOWEVER if I choose the index 1 it works.So what I was thinking was a way to remove all 0s in the array. I am not concerned about the order of the items at all all I am looking for is the smallest integer in the array.
View 8 RepliesI retired recently from a job where we had VS2010 Professional for doing ourdevelopment. Now that I'm retired I can't afford "Pro" and cannot find the component than looks like this (see above). Is/was that component left out of the "Express" version? Do I have to "load" it (and, if so, what name should I look for)? I vaguely remember it being some kind of container for other components.As a follow-up question - can anyone provide a (readable) example of creating a two dimension array of this item I could study?
View 6 RepliesI have the following array
Dim items() = {
New CheckedListBoxItem("NYC", False),
New CheckedListBoxItem("CHI", False),
New CheckedListBoxItem("PHL", False),
New CheckedListBoxItem("SFO", False),
}
I am trying to query against it like this
Try
Dim item As CheckedListBoxItem = items.ToList().Where(Function(x) x.Value = "PHL")
MsgBox(item.Value)
Catch ex As Exception
MsgBox(ex.Message)
End Try
I am getting the error
Value cannot be null.
Parameter name: source
I also tried
Dim item As CheckedListBoxItem = items.FirstOrDefault(Function(x) x.Value.ToString() = "PHL")
I just need to query against the list to get an item and change it's checkedstate from false to true.
Im hearing about this, can someone explain it to me or please show some basic code of Lambda with explanation.
View 2 RepliesCan a LINQ or a LAMBDA expression be used to count the 1's in a binary string ?For example, if I convert a number to its BINARY using.>>
Dim binaryString As String = Convert.ToString( numberVariable, 2 )
1) Without using a loop such as a FOR NEXT loop, can I count the number of 1's in the STRING using LINQ or a LAMBDA expression?
2) Can I get the indexes of where the 1's are at in a collection such as a LIST using LINQ or a LAMBDA expression?I know the syntax of some LINQ expressions, however, I don't know which method may be suitable.
I've come up with the following and it's partly working.
Public serial1, serial2, serial3, serial4, serial5 As SerialPort
Public serialports() As Object = New Object() {serial1, serial2, serial3, serial4, serial5}
dComPort = "COM4"[code]....
The above code works fine! But im having trouble trying to now retreive whats stored in the array.In the above example, an entry will be stored in serialports(4), all other array elements will be blank.If I do this it works.
MsgBox(serialports(4).PortName) ' this retuns the value COM4
But I'd like to loop though all array elements and print out ALL the PortNames, The below code doesnt work, I get an error Object variable or With block variable not set.
For i = 0 To serialports.Length - 1
MsgBox(serialports(i).portname)
Next
Is it possible to shorten the following function to a lambda expression?Or (to do the trick by myself) what is the best and most understandable for beginners tutorial for lambda in vb.net?[code]
View 2 RepliesI have a nested class, let's call it class1 and it has class2 inside it; VB.Net eg:[code]
1) How can I define X number of Class2 objects[let's call it: Node(x) array]** with NEW() subroutine called?' this raises error: dim cls2(n) as new class2 end sub.
2) How can I return actual number of Node() array? [code]Outside my class in main project I define cls1 object:[code]Now an array of class2 is created inside cls1.
3) Now,How can I access All of them[node(x) array which is created inside cls1] with all properties and methods available?
I remember I wrote a ProcessManager class with this functionality in .net 2003, nearly 4 years age, I don't have the code now.
I've been trying to feed a multi line textbox into a string array then check item by item if a string contains part of it.
[Code]...
I have a question about locating a particular object in a generic list. I have 2 lists, one contains a list of every song in a library and the other contains only copies of some the those elements that are added to a playlist. How would I locate and change a value of an particular item in a list by comparing one of their variables such as name? Or find it's index in the masterlist.
View 14 Repliesfind the proper DLL with the OpenSqlFIlestream API objects so i can sue them in VBA/Access. trying to import either sqlnclient.dll or sqlncient10.dll both produce a "Can't add reference to the specified file." error. How do I get these objects into my environment so VBA recognizes and can use them?
View 6 RepliesI want to cycle through a arraylist and for each item in that list I need to create a picturebox, label1, label2 each with specific name attributes
[Code]...
Is it possible to find a complete object in list of objects?
how to find x in list1 if it exists without comparing a single property like ID ?
Given an object instance, how can I recurse its members (i.e. the whole object graph) for an object of a specific type, or one that inherits from a specific type?
View 1 RepliesI am having so trouble with the ToUpper() procedure with strings. I am using LINQ to find unique values in a list of objects. In that whole process I set the values to compare to all lowercase in order to get a proper list. My goal is to populate a dropdown list with the values. I'm attempting to set the first letter of of the string to uppercase and keep the rest lowercase however the toUpper() procedure is not working?
Private Function FixCase(ByVal strIn) As String
Dim strOutput As String
Dim intStringLength As Integer = strIn.Length - 1
strOutput = strIn.Substring(0, 1)
[code].....
I have a list of objects, each object has a score attribute,The list of scores needs to be combined on the player ID to become a totaled score or series. My current thought process is to For Each through the list of individual games, and add the score attribute to a new list of scores with the same objects. So one list would be like:
clsGame(ID Number, Sore)
dim ScoreList as list(of clsGames)
ScoreList.Add(New clsGame(11, 244)
ScoreList.Add(New clsGame(11, 333)
ScoreList.Add(New clsGame(11, 444)
Then go through combining on like ID's to make a new list of games, that would actually be the series.
Dim SeriesList as new list(of clsClasses)
For each game as clsGame in ScoreList
'cycle through the list of series seeing if an ID matches, if so add the score onto that ID
Else
[code]....
Now I don't know how to add the player if its not in the seiries list without doing a heck of a lot more for each statements. If I add it after the end if then it will be added even if it is in the list..I tried playing around with List.Contains method, but I could only see if it contaned the exact same values i.e
SeiresList.Contains(game)
and because the scores are different (series vs single game) it wouldn't match, and I don't know how to see if it contains an object with just one of the attributes the same...
How can i remove an array item by selecting an item from listobx and press remove/delete button?for an example, if i want remove index 2 from listbox, so the array should remove index 2 item and move the item of index 3 to index 2 and so on.
View 7 Repliesok first off my over all goal is to create a simple database program. I need to have an index file that i can search and then load the item data from a path refferenced from the index file. So i was thinking that if I have a IndexClass object, that has the following varribles: name as string, Desc as sting, and ImagePath as String.
[Code]...
I have BIG trouble trying to understand the decleration and creation of an instance with respect to arrays of objects. Basically I struggle with with this error:
Object reference not set to an instance of an object.
complete the test code I made below, so that I can try to understand it..? Been figthing with this for hours..
Code:
Public Class Point
Public x
Public y
[Code].....
I am creating a game which include guns and bullets and I created everything. I want to have a shorter code which I am going to create a array of objects which are the bullets. Can someone help me? In VB6 it's possible to create an array of objects but I am having a hard time for VB 2008.
View 4 RepliesThis is getting on my nerves. All the examples I keep finding deal with Consoles, all I'm trying to do is put data into an array of objects and output them into a Text box, but I don't know the syntax to do that.Here's my class
Public Class Student
Private SID As Integer
Private firstName As String
[code]......
Reverse an array of objects?
View 8 RepliesI have two methods in a class for placing and rotating an array of objects(Pieces) on a Board.pieces have a bounding rectangle and a property called center that is the center point of the rectangle(piece).what i want is to rotate all the pieces in clockwise or counterclockwise direction ,depending on the mouse direction,when the mousebutton is down on any of the pieces other than the center piece and the mouse moves.can anyone modify my code below to achieve this or post some new code that does this. using the rotatepiece() method below in a timerevent with a buttondown event to start the timerrotates all the pieces in clockwise or counterclockwise direction.
Shared PosArray(18) As PointF
Shared Increment As Double
'place pieces in rows [order 3-4-5-4-3]
[code]....
I'm struggling with this Serializing of Data. and I've checked out the MSDN, and saw the Serializing an Array will make the out put like this:
[Code]...
I'd like to create an array of objects with events. Where do I need to put the "WithEvents"? Should it be placed in the ReDim line or the next one?I'm trying to use a "global" event, like objects of people that recieve a time-event to get older.
[Code]...
For example, there are a lot of item in ListBox..so, how can i find the certain item that i need.. Let the item in ListBox as below
1234567899
9987654321
6666666666
8908899889
8678678768
5467676767
so, how can i find 6666666666 without using the scroll bar at ListBox
I'm having a problem at the moment developing my application. What i need to do is find out how many modems they are connected to my system and send data to each one in turn. I have the programme working for one modem at the moment.
So I can send data to a modem that i specify, for example a modem on COM port 1. I have functions already that will give me a list of COM ports that I need to open.My problem is that i want to dynamically create a new modem object along side existing modems and store them in a collection.
[Code]...
I've been wasting so much time on this. Basically I want to have a list of objects and I want to call some specific methods of some specific bjects..g.MsgBox(Instances(0).Position(0).ToString)It should alert a number that presents the X position, but it is not working... the box does not even appear and no errors.
View 8 Replies