I'm looking for a function that will take two parameters (a string and an integer) and print the string on a new line for each count of the integer.
For example, the parameters ("test", 2) would return:
test
test
I'm sure this is a simple bit of code, but I have never worked with VB before.
Any help is greatly appreciated!
#Constuntine had put me on the right path. The code I ended up using was:
Public Function printText(text As String, number As Integer)
dim index as integer
dim s as string = ""
for index = 0 to number
if index = number
s = s + text
else
s = s + text + VBCRLF
end if
Next index
return s
End Function
Here is a basic function that should accomplish what you need
Public Function printNumofTimes(text As String, number As Integer)
for index = 1 to number
Debug.Print text
Next index
End Function
This built-in method comes really close. You just have to provide the "print" action.
Strings.StrDup(count, text + vbCrLf)
Related
I struggling to convert back the BCD to STR, if anyone quickly knows how to do it I really appreciate it.
Public Function strBCDToStr(ByVal shIn As Short) As String
'BCD to Text
Dim m_strTemp As String = ""
For m_iLoop As Integer = 1 To 4
m_strTemp = Chr((shIn Mod 16) + 48) & m_strTemp
shIn = (shIn \ (16S))
Next
strBCDToStr = m_strTemp
End Function
Since we're only dealing with short this works out as a simple mapping to standard hex notation. We can reverse it like this:
Public Function StrToShort(bcd As String) As Short
bcd = bcd.Replace(":", "A").Replace(";", "B").Replace("<", "C").Replace("=","D").Replace(">", "E").Replace("?", "F")
Return Convert.ToInt16(bcd, 16)
End Function
Technically I could even combine those two statements and make this method a one-liner.
See it here for every possible input up to the limit of fiddle:
https://dotnetfiddle.net/bvmdKC
We can also simplify the original code like so:
Public Function ShortToHexStr(input As Short) As String
Return input.ToString("X").
Replace("A", ":").
Replace("B", ";").
Replace("C", "<").
Replace("D", "=").
Replace("E", ">").
Replace("F", "?").
PadLeft( 4, "0"c)
End Function
In my class today I was told change some of my sub-procedures to functions, and when I asked why it's better my teacher struggled to answer, generally, i've always thought that functions should only really be used when a value is returned. In the two examples below; is there one method that should be used over the other, or does it not matter? And if it does matter why?
Thanks in advance.
Method 1 (Sub-Proc):
Sub EncryptString(ByVal unkString, ByRef encryptedString)
For i = 1 To Len(unkString)
encryptedString += "*"
Next
End Sub
Method 2 (Function):
[In main I assign the variable "encryptedString" to this function].
Function encryptString(ByVal unkString) As String
For i = 1 To Len(unkString)
encryptString += "*"
Next
End Function
You've misunderstood what they're trying to tell you. In your Function example there is no difference. What your teacher is expecting is like this:
Function EncryptString(ByVal unkString) As String
Dim encryptedString As String = ""
For i = 1 To Len(unkString)
encryptedString += "*"
Next
Return encryptedString
End Function
This is a cleaner and more reusable way than modifying a field, an argument passed ByRef, or the underlying variable of the function
Your example show one of the multiple reason, who initialize the data is unclear. With your sample code, the first option would append to the passed string while the second would create a new string.
The first method would have to specify if it needs an empty string or explain why it appends. While the second method clearly show that a new string will be returned.
Sub Main()
Dim u, e As String
u = "123"
e = "123"
EncryptString1(u, e)
Console.WriteLine(e) ' Display: 123***
u = "123"
e = "123"
e = encryptString2(u)
Console.WriteLine(e) ' Display: ***
Console.ReadLine()
End Sub
Sub EncryptString1(ByVal unkString As String, ByRef encryptedString As String)
For i As Integer = 1 To Len(unkString)
encryptedString += "*"
Next
End Sub
Function encryptString2(ByVal unkString As String) As String
encryptString2 = ""
For i As Integer = 1 To Len(unkString)
encryptString2 += "*"
Next
End Function
Please have option strict on. Also, personally, I rather create a variable instead of using the function name, use .Length instead of Len() and concatenate with & instead of +.
Function encryptString3(ByVal unkString As String) As String
Dim encryptedString As String = ""
For i As Integer = 1 To unkString.Length
encryptedString &= "*"
Next
Return encryptedString
End Function
Or just use the New operator of the String class.
Dim encryptedString as New String("*"c, unkString.Length)
Well, when I was learning this stuff, it was always to use functions to calculate values and subs to do other stuff. I guess for something very general, it doesn't really matter which methodology you use, as you have illustrated in your example. See the link below for further discussion on this topic.
http://analystcave.com/vba-function-vs-vba-sub-procedures/
Hi I need to change WordCount and CountVowel procedures to functions and create a function to count number of consonants in a string.
I have done these two procedures but I cannot figure out how to do the last part. I am fairly new to programming.
My current code is given below:
Sub Main()
Dim Sentence As String
Console.WriteLine("Sentence Analysis" + vbNewLine + "")
Console.WriteLine("Enter a sentence, then press 'Enter'" + vbNewLine + "")
Sentence = Console.ReadLine()
Console.WriteLine("")
Call WordCount(Sentence)
Call VowelCount(Sentence)
Console.ReadLine()
End Sub
Sub WordCount(ByVal UserInput As String)
Dim Space As String() = UserInput.Split(" ")
Console.WriteLine("There are {0} words", Space.Length)
End Sub
Sub VowelCount(ByVal UserInput As String)
Dim i As Integer
Dim VowelNumber As Integer
Dim Vowels As String = "aeiou"
For i = 1 To Len(UserInput)
If InStr(Vowels, Mid(UserInput, i, 1)) Then
VowelNumber = VowelNumber + 1
End If
Next
Console.WriteLine("There are {0} vowels", VowelNumber)
End Sub
Thanks for your time
I would use the following three functions. Note that WordCount uses RemoveEmptyEntries avoids counting empty words when there are multiple spaces between words.
The other two functions count upper case vowels as vowels, rather than just lower case. They take advantage of the fact that strings can be treated as arrays of Char, and use the Count method to count how many of those Chars meet certain criteria.
Note that the designation of "AEIOU" as vowels may not be correct in all languages, and even in English "Y" is sometimes considered a vowel. You might also need to consider the possibility of accented letters such as "É".
Function WordCount(UserInput As String) As Integer
Return UserInput.Split({" "c}, StringSplitOptions.RemoveEmptyEntries).Length
End Function
Function VowelCount(UserInput As String) As Integer
Return UserInput.Count(Function(c) "aeiouAEIOU".Contains(c))
End Function
Function ConsonantCount(UserInput As String) As Integer
Return UserInput.Count(Function(c) Char.IsLetter(c) And Not "aeiouAEIOU".Contains(c))
End Function
To turn each of your Sub routines into a Function, you need to do three things. First, you need to change the Sub and End Sub keywords to Function and End Function, respectively. So:
Sub MyMethod(input As String)
' ...
End Sub
Becomes:
Function MyMethod(input As String)
' ...
End Function
Next, since it's a function, it needs to return a value, so your Function declaration needs to specify the type of the return value. So, the above example would become:
Function MyMethod(input As String) As Integer
' ...
End Function
Finally, the code in the function must actually specify what the return value will be. In VB.NET, that is accomplished by using the Return keyword, like this:
Function MyMethod(input As String) As Integer
Dim result As Integer
' ...
Return result
End Function
So, to apply that to your example:
Sub WordCount(ByVal UserInput As String)
Dim Space As String() = UserInput.Split(" ")
Console.WriteLine("There are {0} words", Space.Length)
End Sub
Would become:
Function WordCount(userInput As String) As Integer
Dim Space As String() = UserInput.Split(" ")
Return Space.Length
End Sub
Note, ByVal is the default, so you don't need to specify it, and parameter variables, by standard convention in .NET are supposed to be camelCase rather than PascalCase. Then, when you call the method, you can use the return value of the function like this:
Dim count As Integer = WordCount(Sentence)
Console.WriteLine("There are {0} words", count)
As far as counting consonants goes, that will be very similar to your VowelCount method, except that you would give it the list of consonants to look for instead of vowels.
You could use the Regex class. It's designed to search for substrings using patterns, and it's rather fast at it too.
Sub VowelCount(ByVal UserInput As String)
Console.WriteLine("There are {0} vowels", System.Text.RegularExpressions.Regex.Matches(UserInput, "[aeiou]", System.Text.RegularExpressions.RegexOptions.IgnoreCase).Count.ToString())
End Sub
[aeiou] is the pattern used when performing the search. It matches any of the characters you've written inside the brackets.
Example:
http://ideone.com/LEYC30
Read more about Regex:
MSDN - .NET Framework Regular Expressions
MSDN - Regular Expression Language - Quick Reference
VB is no longer a language I use frequently but I don't think I'm going to steer you wrong even without testing this out.
Sub Main()
Dim Sentence As String
Console.WriteLine("Sentence Analysis" + vbNewLine + "")
Console.WriteLine("Enter a sentence, then press 'Enter'" + vbNewLine + "")
Sentence = Console.ReadLine()
Console.WriteLine("")
'usually it's better just let the function calculate a value and do output elsewhere
'so I've commented your original calls so you can see where they used to be
'Call WordCount(Sentence)
Console.WriteLine("There are {0} words", WordCount(Sentence))
'Call VowelCount(Sentence)
Console.WriteLine("There are {0} vowels", VowelCount(Sentence))
Console.ReadLine()
End Sub
Function WordCount(ByVal UserInput As String) As Integer
Dim Space As String() = UserInput.Split(" ")
WordCount = Space.Length
'or just shorten it to one line...
'Return UserInput.Split(" ").Length
End Function
Function VowelCount(ByVal UserInput As String) As Integer
Dim i As Integer
Dim VowelNumber As Integer
Dim Vowels As String = "aeiou"
For i = 1 To Len(UserInput)
If InStr(Vowels, Mid(UserInput, i, 1)) Then
VowelNumber = VowelNumber + 1
End If
Next
VowelCount = VowelNumber
End Function
The most obvious change between a sub and a function is changing the keywords that wrap up the procedure. For this conversation let's just say that's one good word to use for encompassing both concepts since they're very similar and many languages don't really draw such a big distinction.
For Visual Basic's purposes a function needs to return something and that's indicated by the As Integer that I added to the end of both of the function declarations (can't remember if that's the right VB terminology.) Also in VB you return a value to the caller by assigning to the name of the function (also see edit below.) So I replaced those lines that were WriteLines with appropriate assignments. Last I moved those WriteLine statements up into Main. The arguments needed to be changed to use the function return values rather than the variables they originally referenced.
Hopefully I'm not doing your homework for you!
EDIT: Visual Basic underwent a lot of changes to the language during the move to .Net back in the early 2000's. I had forgotten (or possibly not even realized) that the new preferred choice for returning a value is now more in line with languages like C#. So rather than assigning values to WordCount and VowelCount you can just use Return. One difference between the two is that a Return will cause the sub/function to exit at that point even if there is other code afterward. This might be useful inside an if...end if for example. I'm hoping this helps you learn something rather than just being confusing.
EDIT #2: Now that I see the accepted answer and re-read the question it seems there was a small part about counting consonants that got overlooked. At this point I assume this was indeed a classroom exercise and the intended answer was possibly even to derive the consonant count by using the other functions.
Here you go.
Function WordCount(ByVal UserInput As String) As Integer
Dim Space As String() = UserInput.Split(" ")
Return Space.Length
End Function
Function VowelCount(ByVal UserInput As String) As Integer
Dim i As Integer
Dim VowelNumber As Integer
Dim Vowels As String = "aeiou"
For i = 1 To Len(UserInput)
If InStr(Vowels, Mid(UserInput, i, 1)) Then
VowelNumber = VowelNumber + 1
End If
Next
Return VowelNumber
End Function
Function ConsonantCount(ByVal UserInput As String) As Integer
Dim i As Integer
Dim ConsonantNumber As Integer
Dim Consonants As String = "bcdfghjklmnpqrstvwxyz"
For i = 1 To Len(UserInput)
If InStr(Consonants, Mid(UserInput, i, 1)) Then
ConsonantNumber = ConsonantNumber + 1
End If
Next
Return ConsonantNumber
End Function
had a search around and can't find an answer.
I've been tasked with converting a strings capitalization from whatever it is in Be it lower case or upper case and swap them round..
For Example :- Input :- "HeLlO" and Output :- "hElLo"
I understand that i need to use a for loop but have not been able to figure out how to step through each character, check the case and switch it if needs be.
I can make a for loop that counts through and displays the individual characters or a simple If statement to convert the whole string into Upper or lower but if i try to combine the 2 my logic isn't working right.
Can anyone help at all?
Here is one simple way to do it:
Public Function InvertCase(input As String) As String
Dim output As New StringBuilder()
For Each i As Char In input
If Char.IsLower(i) Then
output.Append(Char.ToUpper(i))
ElseIf Char.IsUpper(i) Then
output.Append(Char.ToLower(i))
Else
output.Append(i)
End If
Next
Return output.ToString()
End Function
It just loops through each character in the original string, checks to see what case it is, fixes it, and then appends that fixed character to a new string (via a StringBuilder object).
As Neolisk suggested in the comments below, you could make it cleaner by creating another method which converts a single character, like this:
Public Function InvertCase(input As Char) As Char
If Char.IsLower(input) Then Return Char.ToUpper(input)
If Char.IsUpper(input) Then Return Char.ToLower(input)
Return input
End Function
Public Function InvertCase(input As String) As String
Dim output As New StringBuilder()
For Each i As Char In input
output.Append(InvertCase(i))
Next
Return output.ToString()
End Function
Using that same function for InvertCase(Char), you could also use LINQ, like this:
Public Function InvertCase(input As String) As String
Return New String(input.Select(Function(i) InvertCase(i)).ToArray())
End Function
As a Linq query:
Dim input = "HeLlO"
Dim output = new String(input.Select(Function(c)
Return If(Char.IsLower(c),Char.ToUpper(c),Char.ToLower(c))
End Function).ToArray())
Console.WriteLine(output)
Honestly, who writes loops these days? :-)
I have a csv file I need to parse and get an item out of the middle of it. I have chose string manipulation to do this.
sample input file data would be..
Nick,frog,snake,1234
I can get the last entry "1234" with this code..
line.Substring(line.LastIndexOf(",") + 1)
How would I get the 3rd entry, "snake", with substrings? (what the OP means is: how can I get the third element in the comma-separated string, which happens to be "snake")
If you've stored the text of your file in myInputText, and you want to access the third item, the following will work:
resultString = Strings.Split(myInputText, ",")(2)
You can access any string in the file this way.
How would I get the 3rd entry "snake" with substrings?
The easiest way would obviously be with split:
Dim teststr As String = "Nick,frog,snake,1234"
Dim teststr2 As String = teststr.Split(","c)(2)
A simple function like this, using substring, will do the same thing:
Dim teststr3 As String = GetStr(teststr, 2)
Private Function GetStr(input As String, index As Integer) As String
input += ","
Dim counter As Integer = 0
If index <> 0 Then
Do
input = input.Substring(input.IndexOf(","c)).TrimStart(","c)
counter += 1
Loop Until counter = index
End If
GetStr = input.Substring(0, input.IndexOf(","c))
End Function