I am familiar with this post: How to Return a result from a VBA Function but changing my code does not seem to help.
I want to write a simple function in VBA that allows to lowercase an input sentence. I wrote this:
Private Function Converter(inputText As String) As String
Converter = LCase(inputText)
End Function
Sub test()
Dim new_output As String
new_output = Converter("Henk")
MsgBox (new_output)
End Sub
I tried following the advice I found at another stackoverflow post. I made me change this:
Private Function Converter(inputText As String)
Set outputText = LCase(inputText)
End Function
Sub test()
Dim new_output As String
Set new_output = Converter("Henk")
MsgBox (new_output)
End Sub
However, now I get an error that an object is required. Why does it require an object now? I dont get it...
Set outputText = LCase(inputText)
The Set keyword is reserved for Object data types. Unlike VB.NET, String in VBA is a basic data types.
So you dont Set a variable to a string. Drop the second version of your code altogether. It doesn't make sense. That "advice" was probably in another context.
To fix your first version
1- Assign the returned result to the name of the function Converter
2- It would be beneficial to specify explicitly the return type, as String. Currently it is a Variant that always embeds a String, so better make it explicit:
' vvvvvvvvv
Private Function Converter(inputText As String) As String
Converter = LCase(inputText) ' <------------ assign return to name of function
End Function
Related
VBA Beginner here.
I am trying to pass an array of strings from a subroutine to a function which will then modify each string in the array. However I get the "Type:array or user-defined type expected" error message.
I have tried redefining different data types for the array so it is aligned with the data type entered in the function but to no avail.
Hope you can help! THank you so much!
Below is the dummy code:
Sub text()
Dim haha() As Variant
haha = Array("Tom", "Mary", "Adam")
testing (haha())
MsgBox Join(haha, " ")
End Sub
Function testing(ByRef check() As String) As String()
Dim track As Long
For track = LBound(check) To UBound(check)
check(track) = check(track) & " OMG"
Next
End Function
In orignial code, a string is not the same variant (I believe they both would need to be variant? someone can verify), you dont need the brackets after testing, only need brackets if you are setting to another value e.g.
haha2 = testing(haha())
Below code should be ok
Sub text()
Dim haha()
haha = Array("Tom", "Mary", "Adam")
testing haha()
MsgBox Join(haha, " ")
End Sub
Function testing(ByRef check()) As String
Dim track As Long
For track = LBound(check) To UBound(check)
check(track) = check(track) & " OMG"
Next
End Function
You have a few errors in your code:
There are two ways of invoking methods:
1) with Call keyword - in this case you must give all the parameters in brackets:
Call testing(haha)
2) without Call keyword - in this case you just give your parameters after the name of function:
testing haha
In your code you combined both of them and this is syntax error.
If you pass an array as a parameter to function you don't need to put brackets like that: testing (haha()).
The proper syntax is:
testing(haha)
Function testing requires as a parameter an array of String type, you cannot pass object of other type instead since it causes compile error Type mismatch. Currently you are trying to pass variable haha which is of Variant type.
You can change the type of haha variable to array of strings (to avoid the error described above):
Dim haha() As String
However, in this case you cannot assign the value of function Array to it, since the result of this function is of Variant type.
You would have to replace this code:
haha = Array("Tom", "Mary", "Adam")
with this:
ReDim haha(1 To 3)
haha(1) = "Tom"
haha(2) = "Mary"
haha(3) = "Adam"
A couple of suggestions to improve your code:
Dim haha() As String
You define the type of the entry in the array, not the array itself. Use the way mentioned by mielk to fill the array.
Function Testing(byref check as variant) As String
This will avoid problems with undefined variables. Not clear why you feel that the function should return a string though. Maybe even convert to a Sub instead.
I would like to be able to only pass q as argument to a function, so that the user does not have to enter a string "q".
I have a function defined in a module
Function doThis(val As Variant)
MsgBox CStr(val)
' Here is a comparison of val with other strings and additional code
End
I call it from my worksheet:
=doThis(q)
And the messagebox returns
Error 2029
I have tried with String and Boolean as value type as well, but only variant fires the function.
Is it possible to receive a q as argument?
Quite simple. First create a Defined Name for q
Secondly in a standard module:
Function doThis(val As Variant)
MsgBox CStr(val)
doThis = ""
End Function
Finally in the worksheet:
I want to conditionally append a string, derived from a function, to a string builder. The required condition is that the function is not returning a blank string ("").
The purpose of conditionally appending the string is to avoid AppendLine() appending a line when the string (returned from the function) being appended is empty.
My current code (wrapping the function in a condition calling the very same function):
Dim builder As New System.Text.StringBuilder()
builder.Append("Some text...").AppendLine()
If Not IsNothing(someFunction(someParameterAA, someParameterAB)) Then
builder.Append(someFunction(someParameterAA, someParameterAB)).AppendLine()
End If
If Not IsNothing(someFunction(someParameterBA, someParameterBB)) Then
builder.Append(someFunction(someParameterBA, someParameterBB)).AppendLine()
End If
builder.AppendLine().Append("...some text.")
Dim s As String = builder.ToString
MessageBox.Show(s)
It is my hope that a more efficient alternative exists (efficient in terms of the amount of code to be written). Ultimately, I'd like to avoid calling the same function twice however I cannot independently add the builder.Append line of code to my function. Is it instead possible to target builder.Append?
Example of the potential logic:
If `builder.Append()` inside the following brackets is not an empty string then:
(
builder.Append(someFunction(someParameterAA, someParameterAB)).AppendLine()
)
If anyone has a solution on the above, bear in mind the prequisite of concision (=< 2) lines of code additional to the builder.Append() line.
I'm open to any other suggestions.
Create another method to do the appending like so:
CheckBeforeAppend(someFunction(someParameterAA, someParameterAB), builder)
CheckBeforeAppend(someFunction(someParameterBA, someParameterBB), builder)
....
Public Sub CheckBeforeAppend(s As String, sb As StringBuilder)
If Not String.IsNullOrEmpty(s)
sb.Append(s).AppendLine()
End If
End Sub
A simple refactor such as this shortens your original code and means you don't need to duplicate the null or empty check on the return value of your function.
And for the extension method (place this code in a Module):
<Extension()>
Public Sub CheckBeforeAppend(s As String, sb As StringBuilder)
If Not String.IsNullOrEmpty(s)
sb.Append(s).AppendLine()
End If
End Sub
usage:
someFunction(someParameterAA, someParameterAB).CheckBeforeAppend(sb)
or for an extension on StringBuilder:
<Extension()>
Public Sub CheckBeforeAppend(sb As StringBuilder, s As String)
If Not String.IsNullOrEmpty(s)
sb.Append(s).AppendLine()
End If
End Sub
usage:
builder.CheckBeforeAppend(someFunction(someParameterAA, someParameterAB))
You can avoid calling the function twice by storing the result of the function in a variable.
Dim myString As String = someFunction(someParameterAA, someParameterAB)
If myString <> "" Then
builder.Append(myString).AppendLine()
End If
myString = someFunction(someParameterBA, someParameterBB)
If myString <> "" Then
builder.Append(myString).AppendLine()
End If
This way you just call the function once and check your conditions with the variable. Also the code looks a lot smaller and more understandable.
I am trying to create custom convert cyrillic to latin text function in VB.net. I've never tried to make a custom function so I don't know what I am doing wrong. I have one problem and also, function doesn't work : Object reference not set to an instance of an object.
Public Function ConvertCtoL(ByVal ctol As String) As String
ctol = Replace(ctol, "Б", "B")
ctol = Replace(ctol, "б", "b")
**End Function** ' doesn't return a value on all code paths
Since I didn't found a solution for cyrillic to latin text I was planning to create function that would replace every letter from one alphabet to another.
You need Return ctol to tell it what value to return.
Perhaps researching "lookup table" would help you make a neater function.
Edit: The Wikipedia entry for Lookup table should be a good start.
Here is a simple example:
Imports System.Text
Module Module1
Function ReverseAlphabet(s As String) As String
Dim inputTable() As Char = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".ToCharArray()
Dim outputTable() As Char = "ZYXWVUTSRQPONMLKJIHGFEDBCA".ToCharArray()
Dim sb As New StringBuilder
For Each c As Char In s
Dim inputIndex = Array.IndexOf(inputTable, c)
If inputIndex >= 0 Then
' we found it - look up the value to convert it to.
Dim outputChar = outputTable(inputIndex)
sb.Append(outputChar)
Else
' we don't know what to do with it, so leave it as is.
sb.Append(c)
End If
Next
Return sb.ToString()
End Function
Sub Main()
Console.WriteLine(ReverseAlphabet("ABC4")) ' outputs "ZYX4"
Console.ReadLine()
End Sub
End Module
I have an HTMLElementCollection that I'm going through using a For Each Loop to see if the InnerHTML contains certain words. If they do contain any of those keywords it gets saved into a file.
Everything works fine but I was wondering if there is a way to simplify. Here's a sample
For Each Helement As HtmlElement In elements
If Helement.InnerHtml.Contains("keyword1") Or Helement.InnerHtml.Contains("keyword2") Or Helement.InnerHtml.Contains("keyword3") Or Helement.InnerHtml.Contains("keyword4") Or Helement.InnerHtml.Contains("keyword5") = True Then
' THE CODE TO COPY TO FILE
End If
Next Helement
Does anything exist that would work like:
If Helement.InnerHtml.Contains("keyword1", "keyword2", "keyword3", "keyword4", "keyword5")
The way I'm doing it now just seems wasteful, and I'm pretty OCD about it.
1) One approach would be to match the InnerHtml string against a regular expression containing the keywords as a list of alternatives:
Imports System.Text.RegularExpressions
Dim keywords As New Regex("keyword1|keyword2|keyword3")
...
If keywords.IsMatch(HElement.InnerHtml) Then ...
This should work well if you know all your keywords beforehand.
2) An alternative approach would be to build a list of your keywords and then compare the InnerHtml string against each of the list's elements:
Dim keywords = {"keyword1", "keyword2", "keyword3"}
...
For Each keyword As String In keywords
If HElement.InnerHtml.Contains(keyword) Then ...
Next
Edit: The extension method suggested by Rob would result in more elegant code than the above approach #2, IMO.
You could write an Extension Method to string that provides a multi-input option, such as:
Public Module StringExtensionMethods
Private Sub New()
End Sub
<System.Runtime.CompilerServices.Extension> _
Public Function Contains(ByVal str As String, ByVal ParamArray values As String()) As Boolean
For Each value In values
If str.Contains(value) Then
Return True
End If
Next
Return False
End Function
End Module
You could then call that instead, as in your second example :)
Here's another extension method that cleans up the logic a little with LINQ:
<Extension()>
Public Function MultiContains(str As String, ParamArray values() As String) As Boolean
Return values.Any(Function(val) str.Contains(val))
End Function