Use A Function To Return A List Of Strings?
Oct 5, 2011
Update: I didn't make it clear but I meant this to be a question about where/how I would use a function to return a list of strings when I'm trying to just work with classes.I have a class called Account.
I have data access class called AccountDAO.I have various functions that return lists of objects like GetAllAccounts, GetAccountByID etc.I want to populate a drop down list with just the account names and nothing else. It's proving rather slow when using lists of objects and databinding them to the dropdownlist.
I feel like I should be using a simple "Select Account_Name From blah" type statement and returning a list of strings but I don't know how to work this into my class and data access class.
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Mar 29, 2012
I am trying to call an external C++ function using VB.NET (answers in C# are fine, I can convert back) which returns a list of device names. This comes in the form of a pointer to a null-terminated array of null-terminated char arrays (correct me if I've misunderstood what I'm dealing with) with a function signature:
long GetNames(char*** names)
Most of the answers to similar questions I've found have involved something more like:
long GetNames(char** names, int length)
It appears from what I've read that I need to give it an IntPtr but I'm uncertain as to how this should be initialized, and in my case I don't know the length of the array. At the moment, in the VB module, I have:
<DllImport("MyExternal.dll", CallingConvention:=CallingConvention.Cdecl)> _
Function GetNames(ByRef names as IntPtr) As UInteger
End Function
I've tried calling the function by passing an IntPtr initialized as IntPtr.Zero or using Marshall.AllocHGlobal, but I always get an AccessViolationException.
Any ideas on how I should be calling this function and how I get the return value into a managed string array would be greatly appreciated.
EDIT: I've found a sample function call in native C as follows:
char **tmplist;
GetNames(&tmplist)
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Aug 27, 2009
I have written a function before to delete and update records, but never anything to return values back to my call of the function. Here is my code, and I will try to explain what I'm trying to acheive.
If Not Att1 = "" Then
Attribute1.Text = Att1
Attribute1.Visible = True
ComboBox1.Visible = True
[code]....
That codes goes on up to att20. It works just fine, but it is forever long, and I would like to clean it up.I want to do something like:
Or, should I pass the combobox number also, so that the code can fill the appropriate combobox? Like.comboboxfill(Att1,Combobox1) how to write the function and how to pass back the information or just how to make it work in general?
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Oct 16, 2009
Say I have a List(Of Tag) with Tag being an object. One member of Tag, Tag.Description, is a string, and I want to make a comma-separated concatenation of the Description members.Is there an easier way to do this than to read the Description members into a List(Of String) and then use the Join function?
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Jul 29, 2011
I want the Function to accept List(Of String), Array & String and similarly return List(Of String), Array & String respectively. The Function simply adds a string (month) to the input collection. I just want to use it for string, array and list with needing to think of conversions.
[Code]...
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Mar 31, 2009
I'm working on a program dealing with jagged arrays.Code is below.The FindPath() function works perfectly.It essentially randomly chooses an action from 3 possible choices.The goal of this function is to make it to position (3,3) from (0,0).Sometimes it makes it, sometimes it doesn't.It gives up after 2000 moves.
The PushButton() function is where I have the problem.I want to run the FindPath() function 2000 times, and return the resulting list of moves into intLists()(), my jagged array.I want to use
intRuns = 0
For intRuns = 0 To intLists.GetUpperBound(0)
lstMoveList.Items.Add(intLists(intRuns).GetUpperBound(0)) 'here is where I get the problem.
this section of code to dump the number of attempts it took into a listbox on the main window.I do this at the bottom of the FindPath() function, but that is for testing purposes only.I eventually want to take the successful attempts and manipulate those, so eventually I get the minimum possible number of movements to get from the starting point of (0,0) to the ending point of (3,3).
Function PushButton()
Dim intRuns As Integer
Dim intLists(2000)() As Integer[code]...............
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Aug 5, 2010
I have a list of strings. For each string in that list, I want to prepend another string. I wrote a method to do it, but I was wondering if there was something already in .NET I could use to do this. It seems like something that could be built in, but I was not able to find anything.
Here is the method I wrote:
Private Function PrependToAllInList(ByRef inputList As List(Of String), ByRef prependString As String) As List(Of String)
Dim returnList As List(Of String) = New List(Of String)
For Each inputString As String In inputList
returnList.Add(String.Format("{0}{1}", prependString, inputString))
[code].....
It works, but I would rather use built in functions whenever possible.
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Oct 16, 2009
I'm migrating from VB6 to VB.NET, in hence my questions below:
I have to write a function that returns array of strings.
How can I initiate it to empty array? I need it since I have to check if it's empty array after it returns from this function.
Is list of arrays better for this purpose? If I use a list - Is it empty when it firstly defined? How can I check it it's empty?
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Apr 8, 2011
I got this problem, is there way to use "replace" function to replace multiple strings of same list?
Like;
Dim rList As List(Of String)
rList.Add("A")
rList.Add("B")
[Code]....
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Aug 12, 2011
Private Sub buttoncontrol()
For i As Integer = 1 To 10
(Button&"i").visible = false
[code]....
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Dec 22, 2011
I was wondering if there is a way to get an arraylist returned from strings.split as opposed to a 1-D array. I can't seem to find how to do it.
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Feb 8, 2010
I am using a multililne textbox and I want to take the text typed and merge it with another string. So for example....
CoverPage = Replace(CoverPage,
Me.Note.Replace("{", "{").Replace("}", "}"), txtNote.Text)
Where Me.Note is a string that I am looking for and replacing it with the contents of txtNote.text. And then storing it all back in the string CoverPage.CoverPage is an rtf string that will holds place holders for the text I want to change.(That works) But when i update the note that may have a carriage return in it, the coverpage does not reconize the carriage returns comping from the Multiline textbox when its displayed.I have tried replaceing Enivronment.Newline with vbCr, vbCrl and whatever else I can think of. is there an issue with taking a string carriage control and tranfering it to a rtf carriage control?
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Mar 3, 2011
Just so it's known, this question is mostly academic, even though I tried to use the concept in a real-world solution. I realize the example is contrived, but I believe the concept is valid.I want to write some fluent code like this:
[code]...
I realize that I can't force an anonymous type into a specific type (like implementing an interface or some other class), and I don't want the overhead of defining a specific class just to match my desired fluent name with the actual method name. So I was able to make the code work like this:
copy(my_first_file).to.Invoke(my_second_file)So there is no IntelliSense or type awareness there, and I have to include the Invoke in order to have the method run. How can I get more type safety and exclude the Invoke method, under these constraints: Anonymous Type returned from Method No additional classes or interfaces Preferably, I do not want to pass in another parameter to the copy() method that tells what type to return, unless copy becomes a generic method (but I think that means defining another class/interface, which I don't want to do)
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May 23, 2012
That was probably bad title, but I'll illustrate what I'm trying to do. I have a method in a class that I need to call several times. The method returns a List(Of String). I'm just grabbing some information from a database.
VB.NET
Public Function GetTestList() As List(Of String)
Dim int As Integer = 0
[code]....
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Sep 29, 2009
Can somebody give me hint how to use function Asc() in vb to reverse strings?
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Jun 20, 2012
Basically, I'm trying to do some string manipulation to edit directories. I found some code to try and edit the directories, but when I use it it doesn't recognise 'right' as being a function and only recognises it as a right property, thus producing an error.
I was wondering if there's something I haven't imported or if perhaps 'right' is an obsolete function that was used in VB6 but replaced with something. The code I have is as follows:
[Code]...
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Jun 21, 2009
vb.net
'strSearch = textBox.Text, columns 2 to 10 are the optional columns you want to search to. Function WhereQuery(ByVal strSearch As String, ByVal column1 As String, Optional ByVal column2 As String = "", Optional ByVal column3 As String = "", Optional ByVal column4 As String = "", Optional ByVal column5 As String = "", Optional ByVal column6 As String = "", Optional ByVal column7 As String = "",[code]..
sample output:
im also thinking on using stringbuilder to replace my strings.
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Jul 27, 2010
I have the code below. The code returns a string in (IntersectingPoints) for X and Y. I need X and Y values to be in single and stored in an array to deal with later.[code]...
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Jun 15, 2011
Possible Duplicate: VB.NET Function Return If I have a function that returns a boolean, what is the difference between:Return False and Function = False
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Feb 12, 2010
take a look at the following Code:
Private Sub btnDebug_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDebug.Click
Dim d As Date
[Code]....
The Funtion ZZNull always returns Nothing, so IsNothing(d) in the calling method should evaluate to True.
But it does not !
When you run these lines, then you will see that IsNothing(d) evaluates to False
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Jan 14, 2012
In the documentation of FileInfo.Create Method it says:
'Declaration
Public Function Create As FileStream
'Usage
[code].....
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Mar 8, 2009
So the program I am writing validates the controls on the page on button_click.
I want to write a function which checks which step the program is at (0-7) then return something depending on whether or not it validated.
My plan was to return the control which was not valid.
Private Function ValidateInputs() As Control
Select Case wizardStep
Case 0
[Code].....
1. could I return the names off all the controls which did not validate?
2. should I be returning a control type or would something like a string be better?
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Mar 1, 2012
One over time hours and one week's pay @10 hourly pay. I wanted to display those two in two listboxes 1 and 2.
Public Class Form1
Dim overTimeHours As Double
Dim weekPay As Double
[Code].....
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Jun 2, 2009
how return four value from a function. In general function will return single value but here i am going to return four different values. If possible please tell me how to store the function return values.
[Code]...
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Oct 5, 2010
I've created my own version of HexToDec() to properly handle the negative flag. I saw other versions online that used "Not(value)" to do the Pos/Neg inversion, but that does not generate the proper value... No, it's not the most elegant my any means. But I couldn't find anything online that actually worked.
Long story short, I want to return NaN in the case that the function is passed a string that is not a valid hex string...
How do I do that? Everything I've tried generates a compiler error... (assign return value to double.nan, assign return value to non-numeric, etc)
Existing function is below:
Function HexToDec(ByVal hexStr As String, Optional ByVal signed As Boolean = False) As Long
Dim lngFinal As Long
[Code].....
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Apr 14, 2009
I get the below warning [code]...
To solve it I put a return statement "Return 1" in the code.
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Sep 3, 2009
After reading all the examples for list of T exists and Find and find first, none show how to handle multi-property objects. Below is bare bones example maybe someone could flesh out to show how this should be done.
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim DatePriceList As New List(Of DateAndPrice)
DatePriceList.Add(New DateAndPrice(Date.Parse("1/1/2000"), 10.12))
DatePriceList.Add(New DateAndPrice(Date.Parse("1/2/2000"), 11.12))
[Code]...
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Mar 21, 2009
I would like to write a function GetHashCodeOfList() which returns a hashcode of a list of strings regardless of order. Given 2 lists with the same strings should return the same hashcode.
ArrayList list1 = new ArrayList()
list1.Add("String1");
list1.Add("String2");
[Code].....
I can first sort the list, then combine the sorted list into 1 long string and then call GetHashCode(). However sorting is a slow operation. I can get the hash of each individual string (by calling string.GetHashCode()) in the list, then multiplying all hashes and calling Mod UInt32.MaxValue. For Example: "String1".GetHashCode() * "String2".GetHashCode * ... MOD UInt32.MaxValue. But this results in a number overflow.
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Apr 7, 2011
it seems always at this time I cant figure out how to do something maybe it has something to do with lunchtime.
Im having trouble using a method that is defined by an outside company
This is a link to their integration guide:
[URL]
This is their documentation for the class Im trying to use
OrderQueryWebService Class
This class is for SID in particular and is made for use with the notification methods. This is for the Order Query Web Service specifically, allowing clients to return the status of transactions for their merchant, whenever they want to.
Methods
/ <summary>
/ Pass through the variables required and receive a list of Transaction
objects showing transaction status
[Code].....
The MerchantCode, the MerchantUsername, the MerchantPassword are all good the List is a custom type called SetComHash.Transaction
Everytime I try adding a string to the list such as the transactionNumber and some other values it gives me a type error:
"Value of type string cannot be converted to 'SetcomHash.Transaction'
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Aug 1, 2010
I'm using this for a single value to search for.
intPositionOfApartment = InStr(StrConv(pStringToParse, vbUpperCase), "APT") Is it possible to search for more then one value such as "APT", "UNIT" ?
If yes please show me an example of how it should be coded.
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