I may be incorrectly using the term "Dictionary Array", so please tell me the correct terminology if that is the case. In my code below, what I am referring to as a dictionary array is Dim PdfIndividual(individualCount).
Essentially I am trying to get a lambda function to return a count after it iterates through my dictionary array and finds the value I am trying to get a count for.
I am limited in the framework where this code will eventually run which is why I am using a lambda function in the first place. So while I am sure the code I have presented may not be ideal, I am really just interested in understanding why the error occurs, versus just getting it to work.
Dim relationshipTypeCount As Func(Of Dictionary(Of String, String)(), String, Integer) =
Function(PdfIndividualArray, relationshipType)
Dim dictValue As String = ""
Dim relTypeCountResult As Integer = 0
For Each pdfIndDict As Dictionary(Of String, String) In PdfIndividualArray
pdfIndDict.TryGetValue("RelationshipType", dictValue)
If dictValue = relationshipType Then
relTypeCountResult += 1
End If
Next
Return relTypeCountResult
End Function
Dim individualCount As Integer = 5
Dim relType As String = ""
Dim PdfIndividual(individualCount) As Dictionary(Of String, String)
For i As Integer = 0 To individualCount
If i = 0 Then
relType = "primary"
ElseIf i <= 3 Then
relType = "secondary"
ElseIf i > 3 Then
relType = "guest"
End If
PdfIndividual(i) = New Dictionary(Of String, String)
PdfIndividual(i).Add("RelationshipType", relType)
Dim relCount As Integer = relCount = relationshipTypeCount(PdfIndividual, relType)
Next
The error occurs on the dictionary element in the For...Each of my relationshipTypeCount lambda function.
The error text is:
System.NullReferenceException: 'Object reference not set to an
instance of an object.'
pdfIndDict was Nothing.
Screenshot of the error exception
Depending on your targeted .NET version, you can use the following null-conditional form which is more concise:
For Each pdfIndDict As Dictionary(Of String, String) In PdfIndividualArray
pdfIndDict?.TryGetValue("RelationshipType", dictValue)
If dictValue = relationshipType Then relTypeCountResult += 1
Next pdfIndDict
BTW, you can also use the following null check form:
If pdfIndDict IsNot Nothing Then ...
After debugging further I realized that my issue was that I was iterating over an "array" that had 6 elements, however 5 of the elements were nothing at the time of the first call of the lambda function. So I just needed to add a check that the dictionary element I was handling was not nothing.
For Each pdfIndDict As Dictionary(Of String, String) In PdfIndividualArray
If Not IsNothing(pdfIndDict) Then
pdfIndDict.TryGetValue("RelationshipType", dictValue)
If dictValue = relationshipType Then
relTypeCountResult += 1
End If
End If
Next
Related
I have a problem when I use .count in my 2D String list. This is the code:
If File.Exists(fullPath) = True Then
Dim readText() As String = File.ReadAllLines(fullPath)
Dim s As String
accountCounter = 0
For Each s In readText
accountList.Add(New List(Of String))
accountList.Add(New List(Of String))
accountList.Add(New List(Of String))
accountList(accountCounter).Add(s.Split(",")(0))
accountList(accountCounter).Add(s.Split(",")(1))
accountList(accountCounter).Add(s.Split(",")(2))
accountCounter += 1
Next
print_logs(accountList.count)
End If
The result is this:
{{name,email,password},{name2,email2,password2},{name3,email3,password3},{name4,email4,password4}}
beacuse in the file there are the following lines:
name,email,password
name2,email2,password2
name3,email3,password3
name4,email4,password4
But data is not the problem, the real problem is the Count method, it returns (12). I think that it returns 4 * 3 result, because if I add this in the code:
print_logs(accountList(0).Count)
it correctly returns 3.
So, how can I just return 4?
In this code you create three new rows everytime you do an iteration... If there are four lines in your text files then you will create twelve...
Do this instead :
If File.Exists(fullPath) = True Then
Dim readText() As String = File.ReadAllLines(fullPath)
Dim s As String
accountCounter = 0
For Each s In readText
accountList.Add(New List(Of String))
accountList(accountCounter).Add(s.Split(",")(0))
accountList(accountCounter).Add(s.Split(",")(1))
accountList(accountCounter).Add(s.Split(",")(2))
accountCounter += 1
Next
print_logs(accountList.count)
End If
And if you want to make it even better :
If File.Exists(fullPath) = True Then
Dim readText() As String = File.ReadAllLines(fullPath)
For Each s As String In readText
Dim newList = New List(Of String)
newList.Add(s.Split(",")(0))
newList.Add(s.Split(",")(1))
newList.Add(s.Split(",")(2))
accountList.Add(newList)
Next
print_logs(accountList.count)
End If
When I try to assign _val I get "Object does not match target type."
I verified both PropertyInfo's are system.string. I also found examples of this syntax. Thanks for any help.
Private Function SetAttributesForSplitFiles(ByVal _file As String, ByVal _depHeader As HeaderParse)
Dim _fileMask As New FileMaskExtension()
Dim _type As Type = GetType(HeaderParse.depBackupFileProperties)
For Each _prop As Reflection.PropertyInfo In GetType(OutputMgr.Interface.FileMaskExtension).GetProperties()
Dim _headerProperty As PropertyInfo = _type.GetProperty(_prop.Name)
Dim _val = _headerProperty.GetValue(_depHeader)
_prop.SetValue(_fileMask, _val, Nothing)
Next
SendFileTODepcon(_fileMask, _file)
End Function
It was because the custom class I was using was two layers deep.
This worked.
Dim _val As Object = _headerProperty.GetValue(_depHeader.FileProperties)
I'm trying to save from list field that have more than one data on it, how to save all of it at once?
I've try this code
Dim detail As New Detail
Dim detailBr As New DetailBridge
Dim i As Integer
For i = 0 To lstProduct.Items.Count - 1
detail = detailBr.Insert(Convert.ToInt32(ddlGroup.SelectedValue), lstProduct.Items(i).Value) 'error was here
Next
but I got an error in lstProduct.Items(i).Value the error said
Too many arguments to '...'
I'm not sure what the error is.
can anyone help? Thanks for advice.
UPDATE : detailBr is class and the code is
Public Function Insert(ByVal GroupID As Integer, ByVal ProductID As String) As Boolean
Dim iResult As Integer
Dim arrColumn() As String = {"GroupID", "ProductID"}
Dim arrValue() As Object = {GroupID, ProductID}
oConn.Open()
Dim SQLString As String = GenInsert("DetailGroup", arrColumn, arrValue)
Try
iResult = SCommand.Execute(SQLString, oConn)
Catch ex As Exception
Throw ex
Finally
oConn.Close()
End Try
If iResult > 0 Then
Return True
Else
Return False
End If
End Function
The problem here is with the GenInsert Function. Its last two arguments are arrays.
Dim arrColumn() As String = {"GroupID", "ProductID"}
Dim arrValue() As Object = {GroupID, ProductID}
Dim SQLString As String = GenInsert("DetailGroup", arrColumn, arrValue)
A procedure can define only one parameter array, and it must be the last parameter in the procedure definition. MSDN
In simple words you can have only one parameter as array in GenInsert function either arrColumn or arrValue
However, to solve your current problem you can use two dimensional array as parameter as in passing-two-dimensional-array-through-functions and MSDN: Arrays as Return Values and Parameters
I have a dynamic array of strings DMAs which I declare globally.
Dim DMAs() As String
I ReDim the array and assign values to it in the CreateArrayOf function which is of type String() that returns an array of type String()
DMAs = CreateArrayOf(Sites, 2, "", False)
Public Function CreateArrayOf( _
ByRef arrayFrom() As String, _
Optional ByVal numOfChars As Integer = 2, _
Optional ByVal filterChar As String = "", _
Optional ByVal filterCharIsInteger As Boolean = False _
) As String()
Dim i As Integer, _
j As Integer, _
strn As Variant, _
switch As Boolean, _
strArray() As String
'numOfChars 2 for DMA with no filterChar
'numOfChars 3 for W with filterChar "W"
'numOfChars 3 for A with filterChar "A"
'numofChars 2 for D with filterChar "D"
ReDim strArray(LBound(arrayFrom) To LBound(arrayFrom)) 'required in order to
'not throw error on first iteration
For i = LBound(arrayFrom) To UBound(arrayFrom) 'iterate through each site
switch = False
For Each strn In strArray 'iterate through the array to find whether the
'current site already exists
If strn = Mid(arrayFrom(i), 1, numOfChars) And Not strn = "" Then
switch = True
End If
Next strn
If switch = False Then 'if it doesn't exist add it to the array
ReDim Preserve strArray(1 To UBound(strArray) + 1)
strArray(UBound(strArray) - 1) = Mid(arrayFrom(i), 1, numOfChars)
End If
Next i
CreateArrayOf = strArray 'return the new array
End Function
When I attempt to pass the DMAs array to another function OutputAnArray
Private Sub OutputAnArray(ByRef arrayToOutput() As String)
Dim i As Variant
Dim x As Integer
x = 1
For Each i In arrayToOutput
Cells(x, 6).Value = i
x = x + 1
Next i
End Sub
I get the "Type mismatch: array or user-defined type expected". Throughout the whole process I only mess with string arrays.
If I take the content of the OutputAnArray function and put it in the parent function where I'm calling it from, everything's fine.
Any help is appreciated.
I changed all String definitions to Variants
Private Sub OutputAnArray(ByRef arrayToOutput() As Variant)
The culprit was still there, so then after a whole lot of attempts to get this to compile, I removed the () from the arrayToOutput parameter and it started working.
Private Sub OutputAnArray(ByRef arrayToOutput As Variant) 'fixed
What is still perplexing is the fact that in the following function definition, the () are needed for arrayFrom.
Public Function CreateArrayOf(ByRef arrayFrom() As Variant, _ ...
I really don't get it, if anyone has any idea of an explanation, I'd love to hear it.
From the documentation:
"Arrays of any type can't be returned, but a Variant containing an array can."
If follows that the function "CreateArrayOf" does not return an array of strings: it returns a variant containing an array of strings.
The variant cannot be passed as a parameter to a function expecting an array of strings:
Private Sub OutputAnArray(ByRef arrayToOutput() As String)
It can only be passed to a function expecting a variant:
Private Sub OutputAnArray(ByRef arrayToOutput as Variant)
Conversely, DMA is an array of strings:
Dim DMAs() As String
DMA can be passed to a function expecting an array of strings:
Public Function CreateArrayOf(ByRef arrayFrom() As String, _ .
And finally, "Type mismatch: array or user-defined type expected" is a generic type mismatch message. When you pass an array of the wrong type, or a variant array, and get the error "array expected", it's not particularly helpful.
There is no problem with returning typed arrays from functions or passing typed arrays to functions as arguments. The following works as expected:
Option Explicit
Sub asdfasf()
Dim DMAs() As String
DMAs = CreateAnArray()
OutputAnArray DMAs
End Sub
Private Function CreateAnArray() As String()
Dim arr() As String
ReDim arr(1 To 5)
Dim i As Long
For i = LBound(arr) To UBound(arr)
arr(i) = i
Next
CreateAnArray = arr
End Function
Private Sub OutputAnArray(ByRef arrayToOutput() As String)
Dim i As Long
For i = LBound(arrayToOutput) To UBound(arrayToOutput)
Debug.Print arrayToOutput(i)
Next
End Sub
Now, you never show how you actually pass the DMAs array to OutputAnArray.
I'm willing to make an educated guess that you are doing
OutputAnArray (DMAs)
which will indeed result in
Type mismatch: array or user-defined type expected
You cannot freely put parentheses in that manner. They have special meaning.
If you want parentheses to be used when calling a sub, you must use Call:
Call OutputAnArray(DMAs)
And if you don't care, omit the parentheses like in the example above:
OutputAnArray DMAs
I had the same error while passing an array (of user defined type) as an argument to a function ByRef.
In my case the problem was solved using the keyword "Call" in front of the function or the sub being called.
I don't really understand it, but to me it seems like VBA is trying to interpret the function/sub a couple of different ways in the absence of "Call" - which leads to the error message.
I personally try to avoid converting anything to a variant as long as possible.
I'm trying to count the number of an item in a text file, by counting each instance the item was entered into the file earlier on in the program.
I already have the text read from the file and in a text box. The problem is that my current code was just counting the characters in the textbox and not the number of times my desired word was in the file.
For Each desiredword As String In txtContentofFile.Text
intdesiredword = intdesiredword + 1
txtdesiredwordcount.Text = intdesiredword
Next
This counts the characters in the textbox instead of counting the number of desired words. I tried repeatedly before asking help and searched extensively, but I just don't understand what's wrong with my code. Please help :)
You can use Split Function :
C#:
int count = txtContentofFile.Text.Split(desiredword).Length - 1;
VB.net:
Dim count As Integer = txtContentofFile.Text.Split(desiredword).Length - 1
I prefer to use Regular Expressions in this type of situation. They are very tricky to understand but they are extremely powerful and typically faster than other string manipulation techniques.
Dim AllMatchResults As MatchCollection
Try
Dim RegexObj As New Regex(desiredword)
AllMatchResults = RegexObj.Matches(txtContentofFile.Text)
If AllMatchResults.Count > 0 Then
' Access individual matches using AllMatchResults.Item[]
Else
' Match attempt failed
End If
Catch ex As ArgumentException
'Syntax error in the regular expression
End Try
In your case you are looking for the value from AllMatchResults.Count.
Using a great Regular Expression tool like RegexBuddy to build and test the expressions is a great help too. (The above code snippet was generated by RegexBuddy!)
Try this:
Dim text As String = IO.File.ReadAllText("C:\file.txt")
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)
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.
Try the following code
Function word_frequency(word_ As String, input As String) As Integer
Dim ct = 0
Try
Dim wLEN = word_.Length
Do While input.IndexOf(word_) <> -1
Dim idx = input.IndexOf(word_) + wLEN
ct += 1
input = input.Substring(idx)
Loop
Catch ex As Exception
End Try
Return ct
End Function