What should the results be of the following pseudocode:
Initialize counter to 10
Do while counter < 100
Display counter multiplied by 2
Add 10 to the counter
End loop
I'm thinking: 20, 60, 140
This is my code:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim multiplied As Integer
Dim counter As Integer = 10
Do While counter < 100
multiplied = counter * 2
Label1.Text = Label1.Text & ControlChars.NewLine & multiplied.ToString
counter = multiplied + 10
Loop
End Sub
Thanks guys!!
Display counter multiplied by 2
Nothing in that instruction says to modify the counter. Based on a strict interpretation of your instructions, the output should look like this:
20 40 60 80 100 120 140 160 180
Your code, however, matches the results you expect. If you want code that matches your instructions, do it like this:
Dim counter As Integer = 0
Dim result As New StringBuilder()
Dim delimiter As String = ""
Do While counter < 100
result.Append(delimiter).Append( (counter*2).ToString() )
delimiter = Environment.NewLine
counter += 10
Loop
Label1.Text = result.ToString()
And for fun we could do something like this:
Label1.Text = Enumerable.Range(1, 9)
.Select(Function(i) i * 10)
.Aggregate("", Function(s, i) s = s & i.ToString() & ",")
Related
I am having a problem where I just can't seem to get it to split or even display the message. The message variable is predefined in another part of my code and I have debugged to make sure that the value comes through. I am trying to get it so that every 100 characters it goes onto a new line and with every message it also goes onto a new line.
y = y - 13
messagearray.AddRange(Message.Split(ChrW(100)))
Dim k = messagearray.Count - 1
Dim messagefin As String
messagefin = ""
While k > -1
messagefin = messagefin + vbCrLf + messagearray(k)
k = k - 1
End While
k = 0
Label1.Text = Label1.Text & vbCrLf & messagefin
Label1.Location = New Point(5, 398 + y)
You can use regular expression. It will create the array of strings where every string contains 100 characters. If the amount of remained characters is less than 100, it will match all of them.
Dim input = New String("A", 310)
Dim mc = Regex.Matches(input, ".{1,100}")
For Each m As Match In mc
'// Do something
MsgBox(m.Value)
Next
You can use LINQ to do that.
When you do a Select you can get the index of the item by including a second parameter. Then group the characters by that index divided by the line length so, the first character has index 0, and 0 \ 100 = 0, all the way up to the hundredth char which has index 99: 99 \ 100 = 0. The next hundred chars have 100 \ 100 = 1 to 199 \ 100 = 1, and so on (\ is the integer division operator in VB.NET).
Dim message = New String("A"c, 100)
message &= New String("B"c, 100)
message &= New String("C"c, 99)
Dim lineLength = 100
Dim q = message.Select(Function(c, i) New With {.Char = c, .Idx = i}).
GroupBy(Function(a) a.Idx \ lineLength).
Select(Function(b) String.Join("", b.Select(Function(d) d.Char)))
TextBox1.AppendText(vbCrLf & String.Join(vbCrLf, q))
It is easy to see how to change the line length because it is in a variable with a meaningful name, for example I set it to 50 to get the output
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
You can use String.SubString to do that. Like this
Dim Message As String = "your message here"
Dim MessageList As New List (Of String)
For i As Integer = 0 To Message.Length Step 100
If (Message.Length < i + 100) Then
MessageList.Add(Message.SubString (i, Message.Length - i)
Exit For
Else
MessageList.Add(Message.SubString (i, 100))
End If
Next
Dim k = MessageList.Count - 1
...
Here is what your code produced with a bit of clean up. I ignored the new position of the label.
Private Sub OpCode()
Dim messagearray As New List(Of String) 'I guessed that messagearray was a List(Of T)
messagearray.AddRange(Message.Split(ChrW(100))) 'ChrW(100) is lowercase d
Dim k = messagearray.Count - 1
Dim messagefin As String
messagefin = ""
While k > -1
messagefin = messagefin + vbCrLf + messagearray(k)
k = k - 1
End While
k = 0 'Why reset k? It falls out of scope at End Sub
Label1.Text = Label1.Text & vbCrLf & messagefin
End Sub
I am not sure why you think that splitting a string by lowercase d would have anything to do with getting 100 characters. As you can see the code reversed the order of the list items. It also added a blank line between the existing text in the label (In this case Label1) and the new text.
To accomplish your goal, I first created a List(Of String) to store the chunks. The For loop starts at the beginning of the input string and keeps going to the end increasing by 10 on each iteration.
To avoid an index out of range which would happen at the end. Say, we only had 6 characters left from start index. If we tried to retrieve 10 characters we would have an index out of range.
At the end we join the elements of the string with the separated of new line.
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
BreakInto10CharacterChunks("The quick brown fox jumped over the lazy dogs.")
End Sub
Private Sub BreakInto10CharacterChunks(input As String)
Dim output As New List(Of String)
Dim chunk As String
For StartIndex = 0 To input.Length Step 10
If StartIndex + 10 > input.Length Then
chunk = input.Substring(StartIndex, input.Length - StartIndex)
Else
chunk = input.Substring(StartIndex, 10)
End If
output.Add(chunk)
Next
Label1.Text &= vbCrLf & String.Join(vbCrLf, output)
End Sub
Be sure to look up String.SubString and String.Join to fully understand how these methods work.
https://learn.microsoft.com/en-us/dotnet/api/system.string.substring?view=netframework-4.8
and https://learn.microsoft.com/en-us/dotnet/api/system.string.join?view=netframework-4.8
Have to create a lottery program, getting the random numbers and such easily enough. However I'm stumped. Essentially I have 2 buttons. One to display a checked list box with numbers 1-100, along with the 5 lotto numbers. I have a 2nd button that checks 2 things, to make sure that more than 5 numbers are not checked matching numbers. I'm lost on how to check for a match between the selected numbers between the RNG numbers.
Public Class Form1
Private Sub displayBtn_Click(sender As Object, e As EventArgs) Handles displayBtn.Click
Dim lottoNumbers(5) As Integer
Dim counter As Integer = 0
Dim number As Integer
Dim randomGenerator As New Random(Now.Millisecond)
'This will randomly select 5 unique numbers'
Do While counter < 5
number = randomGenerator.Next(0, 98)
If Array.IndexOf(lottoNumbers, number) = -1 Then
lottoNumbers(counter) = number
counter += 1
End If
Loop
'Display the lottery numbers in the label.'
Label1.Text = String.Empty
Array.Sort(lottoNumbers)
For Each num As Integer In lottoNumbers
Label2.Text = "Lottery Numbers"
Label1.Text &= CStr(num) & " "
Next num
For x = 0 To 98
CheckedListBox1.Items.Add(x + 1)
Next
End Sub
Private Sub checkBtn_Click(sender As Object, e As EventArgs) Handles checkBtn.Click
Dim count As Integer = 0
Dim x As Integer
'Checks to see if user checked more than 5'
For x = 0 To CheckedListBox1.Items.Count - 1
If (CheckedListBox1.CheckedItems.Count > 5) Then
MessageBox.Show("You cannot select more than 5 numbers.")
Return
Else
If (CheckedListBox1.GetItemChecked(x) = True) Then
count = count + 1
ListBox1.Items.Add(CheckedListBox1.Items(x))
End If
End If
Next
End Sub
I'm developing a program that asks the user to input 5 numbers. The lowest of the 5 numbers will be dropped, and then the other 4 numbers are to be averaged.
I'm quite new to VB, but I believe I'm currently on the right path here...
I've sorted the array to help identify the lowest number, but I do not know how to exclude the lowest number and to then average the other remaining 4.
Here is my code so far:
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim IntArr(4) As Integer
Dim i As Integer
For i = 1 To 5
IntArr(4) = InputBox("Enter Number" & i)
Next
Array.Sort(IntArr)
'textbox1.text = ???
End Sub
End Class
Can anyone please assist or at least point me in the right direction?
In keeping with the spirit of your code, something like the following would work.
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim IntArr(4) As Integer
Dim OutArr(3) As Integer
For i = 0 To 4
IntArr(i) = InputBox("Enter Number " & i)
Next
Array.Sort(IntArr)
Array.Copy(IntArr, 1, OutArr, 0, 4) 'exclude the lowest number
TextBox1.Text = OutArr.Average()
End Sub
End Class
Using built in LINQ functions
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim numberOfItems = 5
Dim numberOfItemsToRemove = 1
Dim inArray(numberOfItems - 1) As Integer
Dim outArray(numberOfItems - 1 - numberOfItemsToRemove) As Integer
Dim i As Integer
For i = 0 To numberOfItems - 1
While Not Integer.TryParse(InputBox("Enter Number " & i + 1), inArray(i))
MessageBox.Show("Invalid input!")
End While
Next
outArray = inArray.OrderBy(Function(j) j).Skip(numberOfItemsToRemove).ToArray()
MessageBox.Show(
String.Format(
"Input: [{0}], Output: [{1}], average: {2:0.0}",
String.Join(", ", inArray),
String.Join(", ", outArray),
outArray.Average))
End Sub
Your code as it is above will continue to simply change the value of index 4 with each box if I'm not mistaken. I would do something like this (I will use your variable names for your convenience).
Button1_Click(procedure junk that is auto-inserted)
Dim intArr(4) As Integer
Dim OutArr(3) As Integer
Dim intCounter, intAverage, intLowest, intLowIndex As Integer
'populate all indexes of intArr()
For intCounter = 0 to 4
intArr(intCounter) = InputBox("Please enter a number.")
Next intCounter
intCounter = 1 'reset counter for check
intLowest = intArr(intLowIndex) 'start with index 0
'find lowest number and its index
For intCounter = 1 to 4
If intLowest > intArr(intCounter) Then 'defaults to previous
intLowest = intArr(intCounter)
intLowIndex = intCounter
End If
Next intCounter
intCounter = 0 'reset counter again for possible For...Next loops
Select Case intLowIndex
Case = 0
For intCounter = 0 to 3
OutArr(intCounter) = intArr(intCounter + 1)
Next intCounter
Case = 1
OutArr(0) = intArr(0)
OutArr(1) = intArr(2)
OutArr(2) = intArr(3)
OutArr(3) = intArr(4)
Case = 2
OutArr(0) = intArr(0)
OutArr(1) = intArr(1)
OutArr(2) = intArr(3)
OutArr(3) = intArr(4)
Case = 3
OutArr(0) = intArr(0)
OutArr(1) = intArr(1)
OutArr(2) = intArr(2)
OutArr(3) = intArr(4)
Case = 4
For intCounter = 0 to 3
OutArr(intCounter) = intArr(intCounter)
Next intCounter
End Select
intAverage = (OutArr(0) + OutArr(1) + OutArr(2) + OutArr(3)) / 4
'insert your preferred method to display OutArr() and intAverage
Anyone know why I can not get a new word when the "for" loop reaches the limit?
the intention is that the loop rotate every new word
but something very wrong'm doing
================================
Private Sub getWord()
Static wordCount As Integer
Dim txtLines As String()
txtLines = TextBox1.Text.Split(CChar(vbCrLf))
If (wordCount < txtLines.Count) Then
WebBrowser1.Navigate("http://www.bing.com/search?q=" & txtLines(wordCount) & "&first=1&FORM=PERE")
wordCount = wordCount + 1
End If
End Sub
Dim i As Integer
Dim max As Integer = 40
Private Sub WebBrowser1_DocumentCompleted(sender As Object, e As WebBrowserDocumentCompletedEventArgs) Handles WebBrowser1.DocumentCompleted
If i >= max Then
getWord()
End If
If (WebBrowser1.ReadyState = WebBrowserReadyState.Complete) Then
For i As Integer = 1 To 40 Step 10
WebBrowser1.Navigate("http://www.bing.com/search?q=" & txtLines(wordCount) & "&first=" & i & "&FORM=PERE")
Next
Dim PageElement As HtmlElementCollection = WebBrowser1.Document.GetElementsByTagName("a")
Dim lk As String
For Each lks As HtmlElement In PageElement
lk = lks.GetAttribute("href")
ListBox1.Items.Add(lk)
Next
End If
End Sub
I'm not entirely sure that I understand your question, but I'll take a stab at it.
If you're not getting the expect values from the loop could it be that when you use For i As Integer = 1 To 40 Step 10 that you only get 1, 11, 21, 31, but that you're expecting five values? Perhaps you need to do this:
For i As Integer = 1 To 41 Step 10
I'm trying to loop this array 100 times (gets a number from 0-99,999). I've tried it several different ways with no luck. I've got it set up so you click a button and it generates the array. The user will then enter a number and hit the other button to check how many times that number shows up in the group of a 100 numbers. Any thoughts how to fix it? I'm stuck.
Dim i As Integer
Dim rnd As New Random()
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEnter.Click
Dim num As Integer
If Int32.TryParse(txtEnter.Text, num) AndAlso num >= 0 AndAlso num < 10 Then
lblNumber.Text = i.ToString()
Dim counts = From c In i.ToString()
Group By c Into Group
Select DigitGroup = New With {.Count = Group.Count(), .Digit = c, .Group = Group}
Order By DigitGroup.Count Descending, DigitGroup.Digit
Dim numCount = counts.FirstOrDefault(Function(grp) grp.Digit.ToString() = num.ToString())
If numCount IsNot Nothing Then
Dim numMessage = String.Format("There are {0} number {1}'s found.", numCount.Count, num)
MessageBox.Show(numMessage)
Else
MessageBox.Show("Your number does not contain a " & num)
End If
Else
MessageBox.Show("Please enter a number between 0 and 9.")
End If
End Sub
Private Sub btnGetNumber_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnGetNumber.Click
btnEnter.Enabled = True
i = 0
Do Until i > 100
Dim randomInt = rnd.Next(0, 100000)
i = i + 1
i = rnd.Next(0, 100000)
Loop
End Sub
End Class
First of all, it is common to use For Loops when you know the number of loops.
Secondly, you forgot to increment i in the until loop
Finally, you don't need to redeclare rnd in every loop. Something like that sounds better to me :
Dim rnd As New Random()
For i = 1 To 100
Dim randomInt = rnd.Next( 0 , 100000 )
Next
Move the New Random() out of that loop. Make it global and create the instance just one time.
(The Random generator starts using a seed obtained from the current time. Declaring a Random variable inside a loop result in the same seed used again and again. This gives back the same number defeating the randomness of the function) It is like: http://xkcd.com/221/
See another explanation here
Of course, if you don't increment the variable i used to control the loop, you will loop forever
Dim i As Integer
Dim rnd As New Random()
.....
i = 0
Do Until i > 100
Dim randomInt = rnd.Next(0, 100000)
i = i + 1
Loop
Said that, now I can't get what are you trying to do here. There is no array to check and you do not use the value obtained from the Random generator, simply, your i variable exits with value 101.
Now I am just guessing what are your intentions, but perhaps you want just this?
i = rnd.Next(0, 100000)
This will give to the variable i a random number and your subsequent code checks how many, of the required digit, are present in i
I see that you are not adding the variable "i" to increment:
i = 1
Do Until i > 100
Dim rnd As New Random()
Dim randomInt = rnd.Next(0, 100000)
i+=1 'Increment value of i by 1, same as i = i + 1
Loop
The variable of "i" will always be 1 if not incremented. Check that and let me know if that solves the problem!