I'm trying to make a for loop for will make a new variable for me, every step. I want something like this. What ever step I am on, say, x = 2, it Dims newVar2, if x = 3: Dim newVar3
Is there any way to do that? I was hoping something like, Dim newVar & x would work, but of course now.
I was trying to do it as an array, but I'm not sure how to do that, or ReDimming, so examples would be great!
To create a collection of variable values inside a for loop, you should use a List(Of t) object or something similar (For Example Dictionary).
To do this with a List(Of t) you can do the following :
Dim varList As New List(Of Integer)
For i As Integer = 0 To 10
varList.add(i)
Next
Or if you want to do it with the variable names you mentioned, try :
Dim varList As New List(Of String)
For i As Integer = 0 To 10
varList.add("newVar" & i)
Next
To retrieve the value from a List use the following : Dim result As String = varList(0)
Alternatively you can use a Dictionary object to store Key/Value pairs :
Dim varList As New Dictionary(Of String, Integer)
For i As Integer = 0 To 10
Dim k As Integer = 0
varList.add("newVar" & i, k)
Next
Becareful though as a Dictionary object can only contain unique Keys. To return the value find it as : Dim result As Integer = varList("newVar0")
basic array:
Dim Arr(1000) As Integer
For i As Integer = 0 To 999
Arr(i) = YYYYY
Next
trick for dynamic size:
Dim max As Integer = XXXXXX
Dim Arr(1000) As Integer
For i As Integer = 0 To max
'if too small, Increasing array without loss old data
If Arr.Length = i Then
ReDim Preserve Arr(Arr.Length + 1000)
End If
Arr(i) = YYYYY
Next
or, use list:
Dim max As Integer = XXXXXX
Dim list As New List(Of Integer)
For i As Integer = 0 To max
list.Add(YYYYY)
Next
The other answers are technically correct, but you probably don't need the iteration loops. You can probably do this in a single line of code:
Dim varList As Dictionary(Of String, String) = Enumerable.Range(0, 10).ToDictionary(Function(k) "newVar" & k, Function(v) "Some value for newVar" & v)
Dim myInts As New List(Of Int)
For i = 0 To 10
myInts.Add(i)
Next
Related
I would like all possible combinations from two string arrays.
Both arrays must have same length.
Result must keep order
For example :
dim lStr1() as string = {"One", "Two", "Three"}
dim lStr2() as string = {"EditOne", "EditTwo", "EditThree"}
dim res() as string = myAwesomeFunction(lStr1, lStr2)
// res :
One Two Three
One Two EditThree
One EditTwo Three
One EditTwo EditThree
EditOne Two Three
EditOne Two EditThree
EditOne EditTwo Three
EditOne EditTwo EditThree
It's like the binary composition of 2 arrays of strings.
Here's another solution. Since only 2 arrays are involved, we can bit-fiddle to get all of the "combinations". The & " " is just to format the output to match the example.
Private Function myAwesomeFunction(Array1() As String, Array2() As String) As String()
If Array1.Length <> Array2.Length Then
Throw New ArgumentException("Array lengths must be equal.")
End If
Dim combos(CInt(2 ^ Array1.Length) - 1) As String
For i As Integer = 0 To combos.Count - 1
For j = 0 To Array1.Length - 1
If (i And (1 << j)) > 0 Then
combos(i) += Array2(j) & " "
Else
combos(i) += Array1(j) & " "
End If
Next
Next
Return combos
End Function
The following code will produce the array in your example. It should work for any pair of input arrays. The function checks that the input arrays are of the same length.
The GetPermutations function is taken from a more general class I use for generating permutations of numbers. It returns arrays of total Integers between 0 and choose - 1, and being an Iterator function, it returns the next array each time it is called.
In order to match your example, I returned an array of String where each element is a single string consisting of each of the selected strings separated by spaces. You may find it more useful to return a List(Of String()) or even a List(Of List(Of String))
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim lStr1() As String = {"One", "Two", "Three"}
Dim lStr2() As String = {"EditOne", "EditTwo", "EditThree"}
Dim res() As String = myAwesomeFunction(lStr1, lStr2)
End Sub
Function MyAwesomeFunction(lStr1() As String, lStr2() As String) As String()
Dim combos As New List(Of String)
If lStr1.Length <> lStr2.Length Then Throw New ArgumentException("Arrays must have the same length")
For Each combo() As Integer In GetPermutations(lStr1.Length, 2)
Dim elem As New List(Of String)
For i As Integer = 0 To combo.Length - 1
elem.Add(If(combo(i) = 0, lStr1(i), lStr2(i)))
Next
combos.Add(String.Join(" ", elem))
Next
Return combos.ToArray
End Function
Public Iterator Function GetPermutations(choose As Integer, total As Integer) As IEnumerable(Of Integer())
Dim totals() As Integer = Enumerable.Repeat(Of Integer)(total, choose).ToArray
Dim value(choose - 1) As Integer
Do
Yield value
For index As Integer = choose - 1 To 0 Step -1
value(index) += 1
If value(index) < totals(index) Then Continue Do
value(index) = 0
Next
Exit Do
Loop
End Function
I have written below Code in SSRS Report and calling it from expression as =Code.convertCode(Parameters!ProcessingStatus.Value,"Reject,Fail")).Value , but on previewing report I am getting the error : "Number of indices is less than the number of dimensions of the indexed array"
Public Function convertCode(ParamValues As String, findString As String) As String()
Dim SrcArray() As String
Dim FndArray() As String
Dim DstArray() As String
Dim i As Integer
Dim j As Integer
Dim k As Integer
SrcArray() = Split(ParamValues, ",")
FndArray() = Split(FindString,",")
For k = LBound(FndArray) To UBound(FndArray)
For i = LBound(SrcArray) To UBound(SrcArray)
If (InStr(SrcArray(i), FndArray(k)) > 0) Then
ReDim Preserve DstArray(j) As String
DstArray(j) = SrcArray(i)
j = j + 1
End If
Next i
Next k
arr = DstArray
End Function
At the end of your function you have
arr = DstArray
which should be
convertCode = DstArray
Not sure if that's already the problem.
Note: Option Explicit would prevent this error.
I think the problem is that you're not declaring the first dimension in your arrays.
Dim SrcArray() As String
Dim FndArray() As String
Dim DstArray() As String
Should be:
Dim SrcArray(10) As String
Dim FndArray(10) As String
Dim DstArray(10) As String
Or whatever the number of the Array you'll need.
The error message indicates that the number of indices you have (none) is less that what you need (variables I, k, j).
There any way to compare multiple variables in VBA? For example:
Dim x As Integer
Dim y As Integer
Dim z As Integer
x = 99
y = 2
z = 3
I would like to return the smallest of the values.
I understand I could use select case x > y for all possible permutations but that seems unwieldy for more than 3 variables.
I have tried the worksheet function
solution = Application.WorksheetFunction.Min(x, y, z)
but that returns 2 and I would like it to return the variable name to be passed to another function.
many thanks,
Edit: My apologies if this was confusing, I am still a VBA novice. Here's my problem a little more generally:
I have a list of codes that correspond to names, many names per code. I want to loop through every name per code and count the number of instances that name appears on a list and choose the name with the LEAST occurrences. (could be 0 or could be the same as another name). obviously if there were 2 names it would be easy to do a if x>y then but I'm stumped as for comparing more than 3. Thanks for reading.
Use a public array rather than multiple variables. This will make it easy to iterate through them all and get the highest value, as well as reference the variable with the highest value later on:
Public myArray(0 To 2) As Integer
Public index As Integer
Public Sub calcMin()
Dim i As Integer
Dim maxValue As Integer
myArray(0) = 99
myArray(1) = 2
myArray(2) = 3
For i = 0 To UBound(myArray)
If myArray(i) < maxValue Then
maxValue = myArray(i)
index = i
End If
Next i
End Sub
Function yourFunction(valueToPass As Integer)
'your function's code here
End Function
Then pass the variable to yourFunction like so: yourFunction(myArray(index))
Same idea as Mike's but with an example to call a sub with the min value found:
Sub main()
Dim arrComp(2) As Integer
arrComp(0) = 99
arrComp(1) = 2
arrComp(2) = 3
'It is important to initialize the tmpVal to a value from the array
'to consider the chance where negative and positive values are used
Dim tmpVal As Integer: tmpVal = arrComp(LBound(arrComp))
Dim i As Integer, minIndex As Integer
For i = LBound(arrComp) To UBound(arrComp)
If arrComp(i) < tmpVal Then
tmpVal = arrComp(i)
minIndex = i
End If
Next i
showMinVal arrComp(minIndex)
End Sub
Sub showMinVal(MinVal As Integer)
MsgBox "The min value is " & MinVal
End Sub
Or, a workaround if you want the name associated to the value, you could define a new Type:
'Types must be declared at the top of the module
Type tVarName
varName As String
varVal As Integer
End Type
Sub main()
Dim arrComp(2) As tVarName
arrComp(0).varName = "x"
arrComp(0).varVal = 99
arrComp(1).varName = "y"
arrComp(1).varVal = 2
arrComp(2).varName = "z"
arrComp(2).varVal = 3
Dim tmpVal As Integer: tmpVal = arrComp(LBound(arrComp)).varVal
Dim i As Integer, minIndex As Integer
For i = LBound(arrComp) To UBound(arrComp)
If arrComp(i).varVal < tmpVal Then
tmpVal = arrComp(i).varVal
minIndex = i
End If
Next i
showMinVal arrComp(minIndex)
End Sub
'Sub showing min value along with the name associated to it
Sub showMinVal(MinVal As tVarName)
MsgBox "The min value is " & MinVal.varName & " = " & MinVal.varVal
End Sub
Beginner here, bear with me, I apologize in advance for any mistakes.
It's some homework i'm having a bit of trouble going about.
Overall goal: outputting the specific amount of characters in a string using a loop statement. Example being, user wants to find how many "I" is in "Why did the chicken cross the road?", the answer should be 2.
1) The form/gui has 1 MultiLine textbox and 1 button titled "Search"
2) User enters/copys/pastes text into the Textbox clicks "Search" button
3) Search button opens an InputBox where the user will type in what character(s) they want to search for in the Textbox then presses "Ok"
4) (where I really need help) Using a Loop Statement, The program searches and counts the amount of times the text entered into the Inputbox, appears in the text inside the MultiLine Textbox, then, displays the amount of times the character showed up in a "messagebox.show"
All I have so far
Private Sub Search_btn_Click(sender As System.Object, e As System.EventArgs) Handles Search_btn.Click
Dim counterInt As Integer = 0
Dim charInputStr As String
charInputStr = CStr(InputBox("Enter Search Characters", "Search"))
I would use String.IndexOf(string, int) method to get that. Simple example of concept:
Dim input As String = "Test input string for Test and Testing the Test"
Dim search As String = "Test"
Dim count As Integer = -1
Dim index As Integer = 0
Do
index = input.IndexOf(search, index) + 1
count += 1
Loop While index > 0
count is initialized with -1 because of do-while loop usage - it will be set to 0 even if there is no pattern occurrence in input string.
Try this Code
Dim input As String = "Test input string for Test and Testing the Test"
Dim search() As String = {"Te"}
MsgBox(input.Split(input.Split(search, StringSplitOptions.None), StringSplitOptions.RemoveEmptyEntries).Count)
Concept: Increment the count until the input containing the particular search string. If it contains the search string then replace the first occurance with string.empty (In String.contains() , the search starts from its first index, that is 0)
Dim input As String = "Test input string for Test and Testing the Test"
Dim search As String = "T"
Dim count As Integer = 0
While input.Contains(search) : input = New Regex(search).Replace(input, String.Empty, 1) : count += 1 : End While
MsgBox(count)
Edit:
Another solution:
Dim Input As String = "Test input string for Test and Testing the Test"
Dim Search As String = "Test"
MsgBox((Input.Length - Input.Replace(Search, String.Empty).Length) / Search.Length)
try this code.... untested but i know my vb :)
Function lol(ByVal YourLine As String, ByVal YourSearch As String)
Dim num As Integer = 0
Dim y = YourLine.ToCharArray
Dim z = y.Count
Dim x = 0
Do
Dim l = y(x)
If l = YourSearch Then
num = num + 1
End If
x = x + 1
Loop While x < z
Return num
End Function
Its a function that uses its own counter... for every character in the string it will check if that character is one that you have set (YourSearch) and then it will return the number of items that it found. so in your case it would return 2 because there are two i's in your line.
Hope this helps!
EDIT:
This only works if you are searching for individual Characters not words
You can try with something like this:
Dim sText As String = TextBox1.Text
Dim searchChars() As Char = New Char() {"i"c, "a"c, "x"c}
Dim index, iCont As Integer
index = sText.IndexOfAny(searchChars)
While index >= 0 Then
iCont += 1
index = sText.IndexOfAny(searchChars, index + 1)
End While
Messagebox.Show("Characters found " & iCont & " times in text")
If you want to search for words and the times each one is appearing try this:
Dim text As String = TextBox1.Text
Dim wordsToSearch() As String = New String() {"Hello", "World", "foo"}
Dim words As New List(Of String)()
Dim findings As Dictionary(Of String, List(Of Integer))
'Dividing into words
words.AddRange(text.Split(New String() {" ", Environment.NewLine()}, StringSplitOptions.RemoveEmptyEntries))
findings = SearchWords(words, wordsToSearch)
Console.WriteLine("Number of 'foo': " & findings("foo").Count)
With this function used:
Private Function SearchWords(ByVal allWords As List(Of String), ByVal wordsToSearch() As String) As Dictionary(Of String, List(Of Integer))
Dim dResult As New Dictionary(Of String, List(Of Integer))()
Dim i As Integer = 0
For Each s As String In wordsToSearch
dResult.Add(s, New List(Of Integer))
While i >= 0 AndAlso i < allWords.Count
i = allWords.IndexOf(s, i)
If i >= 0 Then dResult(s).Add(i)
i += 1
End While
Next
Return dResult
End Function
You will have not only the number of occurances, but the index positions in the file, grouped easily in a Dictionary.
Hi I am new to VB and I have problems with using array. My code is like that.
This is class FindFactorsObject.vb
Public Sub FindFactors()
count = 0
temp = Convert.ToInt32(Math.Sqrt(_x))
For i As Integer = 1 To temp
If _x Mod i = 0 Then
ReDim array(count)
array(count) = i
count += 1
End If
Next
So I created an array and stored the results. Now I want to display each value in my array in Form.vb and if it is possible can somebody teach me how to make delay for each of the displayed value. Thanks very much
Always declare your variables, if possible to their exact types, you think they will take care of. When you say 'Now I want to display each value in my array in Form.vb' I understood literally: in the Form so, we will print them on your form
Public Sub FindFactors(_x As Integer)
Dim temp As Integer = Convert.ToInt32(Math.Sqrt(_x))
Dim l As New List(Of Integer)
For i As Integer = 1 To temp
If _x Mod i = 0 Then
l.add(i)
End If
Next
Dim pf As New PointF(20, 20)
For Each i As Integer In l
creategraphics.drawstring(i.ToString, New font(font.fontFamily, 24), brushes.cadetblue, pf)
pf = New PointF(pf.X, pf.Y + 30)
Next
End Sub