I'm doing my first project attempting to bind data from an .MDB file to a Windows Form project in Visual Basic. Most of the functions work off an arrays "Hubs", so I wanted to fill this array with information drawn from my database. After using the wizard to create DataSet, I created the following code.
Public Sub LoadData()
For i As Integer = 0 To 15
With Hubs(i)
.ID = HubsDataSet.Tables("Hubs").Rows(i).Item(1).ToString 'This line is flagged as bad by the unit tests.
.City = HubsDataSet.Tables("Hubs").Rows(i).Item(2).ToString
.Lat = HubsDataSet.Tables("Hubs").Rows(i).Item(3).ToString
.Lon = HubsDataSet.Tables("Hubs").Rows(i).Item(4).ToString
End With
Next
'Load ID1ComboBox List
For i As Integer = 0 To 15
ID1ComboBox.Items.Add(Hubs(i).ID)
Next
'Load ID2ComboBox List
For i As Integer = 0 To 15
ID2ComboBox.Items.Add(Hubs(i).ID)
Next
'Set default values for Combo boxes
ID1ComboBox.SelectedIndex = 0
ID2ComboBox.SelectedIndex = 1
End Sub
While the project appears to run and function properly, I now find that all my unit tests fail, throwing an error that no Row 0 exists. In addition, if I attempt to use a for each statement instead of a for loop, the program no longer functions (it skips the lines entirely, since it does not hit a break point I inserted). I'm new to this and very confused what I'm doing wrong.
Related
I am used to assigning ranges to arrays. However, for some reason right now I am constantly getting an application or object defined error (the first code line below). The second line below works fine. It is identical to the first line except I just copy the range showing all the variables exist.
I have checked in the watch window, arrActuals is Variant/Variant(). Adding .Value at the end of the first line did not solve the error either. Any ideas on why this is happening?
arrActuals = wkbOVHFile.Sheets(szAOPPage).Range(Cells(iStartCopy, IntActOVHCol), Cells(iEndCopy, IntActOVHCol))
wkbOVHFile.Sheets(szAOPPage).Range(Cells(iStartCopy, IntActOVHCol), Cells(iEndCopy, IntActOVHCol)).Copy
Cells without a qualifying worksheet object defaults to the active sheet, so your code fails when wkbOVHFile.Sheets(szAOPPage) is not the active sheet.
More robust like this:
Dim rng As Range
With wkbOVHFile.Sheets(szAOPPage)
Set rng = .Range(.Cells(iStartCopy, IntActOVHCol), _
.Cells(iEndCopy, IntActOVHCol))
End With
arrActuals = rng.Value
rng.Copy
I have an array, and it used to work just fine in VBA. I am now using SeleniumBasic and am trying to find the equivalent of the command ".length"
Dim i As Object
Dim elmCollection As Object
Set elmCollection = WDrv.FindElementsByTag("table")
For i = 0 To (elmCollection.Length)
It bombs out on the "For" statement. So, is there an equivalent to the ".length" in SeleniumBasic?
In visual basic it's ubound(array) to get the upper boundary of an array.
You'll want to use:
For i = 0 To ubound(elmCollection)
Selenium basic WebElements collections IIRC start at 1 and the appropriate property is .Count. You are not working with an array.
Therefore your loop should in fact be a For Each, e.g.
Dim i As Object: For Each i In elmCollection
to enumerate through the WebElements collection; if using the slower method of enumeration with objects then you want For i = 1 to elmCollection.Count
I have been working on a project, and am attempting to make a new array for data. I have tried making an empty array with Dim Name() As String = {}. I am using a ListView, and the way I have done it there are blank spots where I have gotten rid of data. This is my current code:
Sub English(ByVal Country() As String, ByVal Language() As String)
rbDisplayallData.Checked = False
lstResults.Visible = True
lstResults.Items.Clear()
lstResults.Columns.Clear()
With lstResults
.View = View.Details
.Columns.Add("English Speaking Countries", 200, HorizontalAlignment.Left)
End With
For i = 0 To 181
Dim EnglishSpeakingCountries(i) As String
If Language(i) = "English" Then
EnglishSpeakingCountries(i) = Country(i)
End If
lstResults.Items.Add(New ListViewItem({EnglishSpeakingCountries(i)}))
Next
End Sub
I am trying to get rid of these spaces.
I Was thinking if I were to compact the array or make a new one with the same data going into a new array it would fix the issue.
If you have a solution please let me know.
There are two things that could be considered an empty array
An array with no elements, i.e. a Length of zero.
An array where every element is Nothing.
All arrays are fixed-length. Once you create an array with a particular number of elements, it always has that number of elements. You can use ReDim Preserve or Array.Resize but, in both those cases, what actually happens is that a new array is created and the elements copied from the old array. The new array is assigned to the same variable but anywhere the old array is referenced, it will still have that same number of elements. Try running this code to see that in action:
Dim a1 As String() = {}
Dim a2 As String() = {"First", "Second", "Third"}
Dim b1 = a1
Dim b2 = a2
Console.WriteLine(a1.Length)
Console.WriteLine(a2.Length)
Console.WriteLine(b1.Length)
Console.WriteLine(b2.Length)
Console.WriteLine()
ReDim Preserve a1(2)
Array.Resize(a2, 6)
Console.WriteLine(a1.Length)
Console.WriteLine(a2.Length)
Console.WriteLine(b1.Length)
Console.WriteLine(b2.Length)
Console.ReadLine()
Output:
0
3
0
3
3
6
0
3
As you'll be able to see, a1 and a2 end up referring to new arrays with the specified lengths but the original arrays with the original lengths still exist and are still accessible via b1 and b2.
If you start with an array with no elements then you can use ReDim Preserve or Array.Resize to give the appearance of resizing the array but that's not really what's happening and that should generally be avoided. If you know how many elements you'll end up with then you could create an array of that size and then set each element in turn. You'd need to keep track of the next element index though, so that's still a bit tedious.
Generally speaking, if you want an array-like data structure but you want it to be able to grow and shrink as required, you should use a collection. The most common collection is the List(Of T), where T is any type you care to specify in your code. If you want to store String objects then use a List(Of String). You can call Add to append a new item to the end of the list, as well as Insert, Remove and RemoveAt methods. You can also get or set an item by index, just as you can do for array elements.
Note that a List(Of T) actually uses an array internally and uses the aforementioned method of "resizing" that array. It optimises the process somewhat though, which makes the code easier for you to write and large collections more efficient to use.
It's worth noting that, in your own code, the Columns and Items properties of your ListView are both collections, although they are slightly different to the List(Of T) class.
Looking at your original code, this:
For i = 0 To 181
Dim EnglishSpeakingCountries(i) As String
If Language(i) = "English" Then
EnglishSpeakingCountries(i) = Country(i)
End If
lstResults.Items.Add(New ListViewItem({EnglishSpeakingCountries(i)}))
Next
could be changed to this:
Dim englishSpeakingCountries As New List(Of String)
For i = 0 To 181
If Language(i) = "English" Then
englishSpeakingCountries.Add(Country(i))
lstResults.Items.Add(Countries(i))
End If
Next
Note that you're just adding items to two collections. I guess the question is whether you actually need this extra collection at all. If you do want to use it later then you need to assign it to a member variable rather than a local variable. If you don't need it later then don't create it at all. As I said, you're already adding items to a collection in the ListView. Maybe that's all you need, but you haven't provided enough info for us to know.
Dim bmpNew As Bitmap = Nothing
Dim Bitmaps(15) As Bitmap
For b = 0 To Bitmaps.Count - 1
If Bitmaps.Contains(bmpNew) Then
Else
If Bitmaps(b) Is Nothing Then
If Bitmaps(b) Is bmpNew Then
Else
Bitmaps(b) = bmpNew
End If
Else
End If
End If
ListBox1.Items.Add(b)
Next
I am developing an application that generates random images every time the button is pressed. After generating the image, it loops through an array of bitmaps which are initially empty. What it should do is fill the array with every new image that it creates while making sure to not add it if it already exists in the array. I have tried many attempts and this method is the only one that actually makes sense and is very close to what I am trying to achieve, but it still produces duplicates in my array.
What am I missing?
I simply want to fill-up cells in my spreadsheet from a VBA function. By example, I would like to type =FillHere() in a cell, and in result I will have a few cells filled-up with some data.
I tried with such a function:
Function FillHere()
Dim rngCaller As Range
Set rngCaller = Application.Caller
rngCaller.Cells(1, 1) = "HELLO"
rngCaller.Cells(1, 2) = "WORLD"
End Function
It breaks as soon as I try to modify the range. Then I tried this (even it's not really the behavior I'm looking for):
Function FillHere()
Dim rngCaller As Range
Cells(1, 1) = "HELLO"
Cells(1, 2) = "WORLD"
End Function
This is not working neither. But it works if I start this function from VBA using F5! It seems it's not possible to modify anything on the spreadsheet while calling a function... some libraries do that though...
I also tried (in fact it was my first idea) to return a array from the function. The problem is that I only get the first element in the array (there is a trick that implies to select a whole area with the formula at the top left corner + F2 + CTRL-SHIFT-ENTER, but that means the user needs to know by advance the size of the array).
I'm really stuck with this problem. I'm not the final end-user so I need something very easy to use, with, preferably, no argument at all.
PS: I'm sorry I asked this question already, but I wasn't registered at that time and it seems that I can't participate to the other thread anymore.
You will need to do this in two steps:
Change your module to be something like:
Dim lastCall As Variant
Dim lastOutput() As Variant
Function FillHere()
Dim outputArray() As Variant
ReDim outputArray(1 To 1, 1 To 2)
outputArray(1, 1) = "HELLO"
outputArray(1, 2) = "WORLD"
lastOutput = outputArray
Set lastCall = Application.Caller
FillHere = outputArray(1, 1)
End Function
Public Sub WriteBack()
If IsEmpty(lastCall) Then Exit Sub
If lastCall Is Nothing Then Exit Sub
For i = 1 To UBound(lastOutput, 1)
For j = 1 To UBound(lastOutput, 2)
If (i <> 1 Or j <> 1) Then
lastCall.Cells(i, j).Value = lastOutput(i, j)
End If
Next
Next
Set lastCall = Nothing
End Sub
Then in order to call the Sub go into the ThisWorkbook area in VBA and add something like:
Private Sub Workbook_SheetCalculate(ByVal Sh As Object)
Call WriteBack
End Sub
What this does is return the value of the topleft cell and then after calculation completes populates the rest. The way I wrote this it assumes only one FillHere function will be called at a time. If you want to have multiple ones which recalculate at the same time then you will need a more complicated set of global variables.
One word of warning is that this will not care what it overwrites when it populates the other cells.
Edit:
If you want to do this on a Application wide basis in an XLA. The code for the ThisWorkbook area should be something like:
Private WithEvents App As Application
Private Sub App_SheetCalculate(ByVal Sh As Object)
Call WriteBack
End Sub
Private Sub Workbook_Open()
Set App = Application
End Sub
This will wire up the Application Level calculation.
What you're trying to do won't work in Excel - this is by design.
You can do this, though:
Function FillHere()
Redim outputArray(1 To 1, 1 To 2)
outputArray(1, 1) = "HELLO"
outputArray(1, 2) = "WORLD"
FillHere = outputArray
End Function
If you then select two adjacent cells in your worksheet, enter =FillHere() and press Control+Shift+Enter (to apply as an array formula) then you should see your desired output.
Fundamentally, a function can only affect the cell it is called from. It sounds like you may need to look at using the Worksheet_Change or Worksheet_SelectionChange events to trigger the modification of cells in the intended range.
You can do this indirectly using a 2-stage process:
Write your UDF so that it stores data in a sufficiently persistent way (for example global arrrays).
then have an Addin that contains application events that fire after each calculation event, looks at any data stored by the UDFs and then rewrites the neccessary cells (with warning messages about overwrite if appropriate) and reset the stored data.
This way the user does not need to have any code in their workbook.
I think (but do not know for sure) that this is the technique used by Bloomberg etc.