I need a bit of help with this insertion sort, The code I have so far is this:
Private Sub SortedList_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim currentitem As Integer = 2
While currentitem <= numitems
currentdataitem = frmEntry.starname(currentitem)
comparison = 1
finish = False
While comparison < currentitem And finish = False
If currentdataitem < frmEntry.starname(comparison) Then
shuffleitem = currentitem
While shuffleitem > comparison
frmEntry.starname(shuffleitem) = frmEntry.starname(shuffleitem - 1)
shuffleitem = shuffleitem - 1
End While
frmEntry.starname(comparison) = currentdataitem
finish = True
End If
comparison = comparison + 1
End While
currentitem = currentitem + 1
End While
arrayindex = 0
For Me.arrayindex = 1 To numitems
lstsorted.Items.Clear()
lstsorted.Items.Add(frmEntry.starname(arrayindex))
lstsorted.Items.Add(frmEntry.DOB(arrayindex))
lstsorted.Items.Add(frmEntry.rank(arrayindex))
Next
End Sub
This insertion sorts their names, but I also need to take their DOB and their rank with it, at what point in my visual basic code do I put this?
You can move the corresponding elements of DOB and Rank whenever you move the elements of starname.
Related
Dears,
I'm looking for assistance in visual basic with respect to multiple choices questions (MCQ).
by using visual basic for Visual Studio 2015
apply the codes without using database:
1- how to Not make any duplications in the questions?(for memorizing purpose... what is wrong and what is right?) E.g. Assuming I open the program and the first question is the word “rich” ,and I chose the correct answer, which is “IT”, I don’t want to see “rich” again until I finish with the whole list. However, if I make the wrong choice for “rich” for anything else e.g. “HR”, I want the word “rich” to appear after a while until I get the question correct. The point here to make the person memorize “rich” is “IT”.
Please write the codes down in your comment (the point you answering)
sorry for asking long question
Thank you
Public Class Form1
Private Structure questionsNanswers
Public Q As String
Public A As String
Public QT As Integer
Public QC As Integer
End Structure
Private wstart As Integer = 0
Private adad As Integer = 10
Private QA(9999) As questionsNanswers
Private word(15) As String
Private aray(15) As Integer
Private Sub RandomizeArray(a As Integer, ByRef array() As Integer)
Dim i As Integer
Dim j As Integer
Dim tmp As Integer
Randomize()
For i = 0 To a - 1
j = Int((6 - i + 1) * Rnd() + i)
tmp = array(i)
array(i) = array(j)
array(j) = tmp
Next
End Sub
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
' next
CheckEntry()
wstart = wstart + 1
If wstart >= adad Then
wstart = 0
End If
WriteText()
End Sub
Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click
' previous
CheckEntry()
wstart = wstart - 1
If wstart < 0 Then
wstart = adad - 1
End If
WriteText()
End Sub
Private Sub CheckEntry()
RadioButton1.Visible = True
RadioButton2.Visible = True
RadioButton3.Visible = True
RadioButton4.Visible = True
RadioButton1.ForeColor = Color.Black
RadioButton2.ForeColor = Color.Black
RadioButton3.ForeColor = Color.Black
RadioButton4.ForeColor = Color.Black
RadioButton1.Checked = False
RadioButton2.Checked = False
RadioButton3.Checked = False
RadioButton4.Checked = False
End Sub
Private Sub WriteText()
Dim out As Boolean = False
For kk = 0 To 6
aray(kk) = kk
Next
RandomizeArray(7, aray)
Do Until out
For j = 0 To 3
If out = False Then
If aray(j) = QA(wstart).QT Then
out = True
Exit Do
End If
End If
Next
For kkk = 0 To 6
aray(kkk) = kkk
Next
RandomizeArray(7, aray)
Loop
RadioButton1.Text = word(aray(0))
RadioButton2.Text = word(aray(1))
RadioButton3.Text = word(aray(2))
RadioButton4.Text = word(aray(3))
Label1.Text = CStr(wstart + 1) & ") " & QA(wstart).Q
' ==============================
Dim go As Boolean = False
If go Then
Dim msg As String
For ll = 0 To 6
msg = msg + CStr(aray(ll)) + "|"
Next
MsgBox(msg)
End If
End Sub
Public Sub New()
' This call is required by the designer.
InitializeComponent()
' Add any initialization after the InitializeComponent() call.
word(0) = "TA"
word(1) = "GR"
word(2) = "HR"
word(3) = "FIN"
word(4) = "commercial"
word(5) = "Proc"
word(6) = "IT"
QA(0).Q = "rich"
QA(0).A = word(6)
QA(0).QT = 6
QA(0).QC = -1
QA(1).Q = "Tal"
QA(1).A = word(1)
QA(1).QT = 1
QA(1).QC = -1
QA(2).Q = "sau"
QA(2).A = word(2)
QA(2).QT = 2
QA(2).QC = -1
QA(3).Q = "pat"
QA(3).A = word(3)
QA(3).QT = 3
QA(3).QC = -1
QA(4).Q = "del"
QA(4).A = word(5)
QA(4).QT = 5
QA(4).QC = -1
WriteText()
End Sub
End Class
Procedures :
1•Store the questions in a database(E.g. MySql/MSSQL/EXCEL)
2•In the database, create a table of 6 columns(column 1 for questions,column 2 for mcq option1,column 3 for mcq option 2, column 4 for mcq option 3,column 5 for mcq option 4 and finally column 6 for mcq answer )
3•Add 1 label and 4 Radio buttons
Now all you have to do is follow this and use the code..
That'll do the work
This question already has answers here:
What is a NullReferenceException, and how do I fix it?
(27 answers)
Closed 7 years ago.
I have a program that creates a list of 25 random numbers from 0 to 1,000. I have to buttons the first button will load a list box with the random numbers and the second button will sort the list of numbers from the smallest to largest which is where I implemented bubble sort code. Now the other list box that is supposed to hold the sorted numbers doesn't work properly it only shows one number instead of all of them.
Here is my code:
Option Strict On
Public Class Form1
Dim rn As Random = New Random
Dim Clicked As Long = 0
Dim numbers, sort As Long
Private Sub GenerateBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles GenerateBtn.Click
Clicked += 1
For x = 0 To 25
numbers = rn.Next(0, 1000)
RandomBox.Items.Add(numbers)
If Clicked >= 2 Then
RandomBox.Items.Clear()
Clicked = 1
End If
Next
End Sub
Private Sub SortBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SortBtn.Click
Dim Sorted() As Long = {numbers}
Dim Swapped As Boolean
Dim endOfArray As Integer = Sorted.Length - 1
Dim Tmp As Byte
While (Swapped)
Swapped = False
For I = 0 To endOfArray - 1
If Sorted(I) > Sorted(I + 1) Then
Tmp = CByte(Sorted(I))
Sorted(I) = Sorted(I + 1)
Sorted(I + 1) = Tmp
Swapped = True
End If
endOfArray = endOfArray - 1
Next
End While
SortBox.Items.Clear()
For I = 0 To Sorted.Count - 1
SortBox.Items.Add(Sorted(I))
Next
End Sub
End Class
Change your:
Dim Sorted() As Long = {numbers}
to
Sorted(x) = numbers
edit: Since you changed your code. You need to put back in the line that loads the Sorted Array.
For x = 0 To 25
numbers = rn.Next(0, 1000)
RandomBox.Items.Add(numbers)
Sorted(x) = numbers
If Clicked >= 2 Then
RandomBox.Items.Clear()
Clicked = 1
End If
Next
and remove the:
Dim Sorted() As Long = {numbers}
from the second part and put this declaration back in the beginning like you had:
Dim Sorted(26) as Long
The way you have will only show the latest random number. It is not any array but a single entity. Therefore only the latest will be add into the array. You need to load each number into the array as you create each one. Thus the (x) which loads it into position x.
You didn't use any arrays at all in your project...you're using the ListBox as your storage medium and that's a really bad practice.
I recommend you set it up like this instead:
Public Class Form1
Private rn As New Random
Private numbers(24) As Integer ' 0 to 24 = 25 length
Private Sub GenerateBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles GenerateBtn.Click
For x As Integer = 0 To numbers.Length - 1
numbers(x) = rn.Next(0, 1000)
Next
' reset the listbox datasource to view the random numbers
RandomBox.DataSource = Nothing
RandomBox.DataSource = numbers
' empty out the sorted listbox
SortBox.DataSource = Nothing
End Sub
Private Sub SortBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SortBtn.Click
' make a COPY of the original array that we will sort:
Dim sorted(numbers.Length - 1) As Integer
Array.Copy(numbers, sorted, numbers.Length)
Dim Swapped As Boolean = True
Dim endOfArray As Integer = Sorted.Length - 1
Dim Tmp As Integer
While (Swapped)
Swapped = False
For I As Integer = 0 To endOfArray - 1
If sorted(I) > sorted(I + 1) Then
Tmp = sorted(I)
sorted(I) = sorted(I + 1)
sorted(I + 1) = Tmp
Swapped = True
End If
Next
endOfArray = endOfArray - 1
End While
' reset the listbox datasource to view the sorted numbers
SortBox.DataSource = Nothing
SortBox.DataSource = sorted
End Sub
End Class
Also, note that you were decrementing endOfArray inside your for loop. You should only decrement it after each pass; so outside the for loop, but inside the while loop.
Additionally, you were using a Tmp variable of type Byte, but generating numbers between 0 and 999 (inclusive). The Byte type can only hold values between 0 and 255 (inclusive).
Your Bubble Sort implementation was very close to correct!
This may be a simple question, but I'm having a real mental block on it. I'm trying to track the index of a Report in my reportList (of Report type) when navigating forwards and backwards through the list.
I've done this one way by assigning the index of the selected item in a combobox. However I also need to do it directly from the list (already filled), with the only input of the user being the next and previous buttons.
Where I set the Report:
If wantFixture = True Then
ind = UC_Menu_Scout1.cmbSelectedPlayer.SelectedIndex
Else
ind = reportList(0) 'index of item in reportList-
'this doesn't work because reportList is of type Report, not integer
End If
reportList.Clear()
reportList = retrieveReport()
'*****General Information
UC_Menu_Scout1.lblRptPosition.Text = reportList(ind).PositionPlayed
Where the next Report can be navigated to:
Private Sub btnNextPlayer_Click(sender As System.Object, e As System.EventArgs) Handles btnNextPlayer.Click
'Moves to next item in playerList
Dim x As Integer = cmbSelectedPlayer.SelectedIndex
If x = cmbSelectedPlayer.Items.Count - 1 Then
x = 0
Else
x += 1
End If
cmbSelectedPlayer.SelectedIndex = x
lblNumberOfReports.Text = "Report: " & x + 1 & "/" & cmbSelectedPlayer.Items.Count
End Sub
Store the current index and report in variables.
Class level variables:
Private curIndex As Integer = 0
Private curReport As Report = Nothing
Next button:
If Not curIndex = reportList.Count - 1 Then
curIndex += 1
End If
curReport = reportList.ElementAt(curIndex)
Previous button:
If Not curIndex = 0 Then
curIndex -= 1
End If
curReport = reportList.ElementAt(curIndex)
I have a button in my program that grabs a bunch of information from a DataGridView object (volume, url, delay, etc) and using that, it plays a file. I'm trying to get the delay to work (wait x number of seconds before playing) and I'm pretty it will work, but whenever I press the button, the play starts immediately. There is no Ctlcontrols.play() anywhere in the program except after the delay, so I have no idea what is causing it to play.
I explained my problem a little bit more in comments. Sorry if I didn't explain my code very well. If you could just tell my what else could be causing my player to start immediately, that would probably be enough.
'snd_btn_go is the button that is supposed to start it.
'This sub doesn't matter as much for the problem, it will just go to SndCueGO() if both numbers are in the valid range.
Private Sub snd_btn_go_Click(sender As Object, e As EventArgs) Handles snd_btn_go.Click
Dim cue1 As Integer
Dim cue2 As Integer
cue1 = If(Integer.TryParse(snd_txt_cue_1.Text, cue1), Int(snd_txt_cue_1.Text), snd_num1)
If snd_txt_cue_2.Text <> "" Then
cue2 = If(Integer.TryParse(snd_txt_cue_2.Text, cue2), Int(snd_txt_cue_2.Text), snd_num2)
Else
cue2 = -1
End If
If (cue1 <= dgSound.Rows.Count - 1 And cue1 > 0) Then
SndCueGO(cue1, cue2)
End If
End Sub
'This sub pulls all the info from the correct row in the DataGrid and assigns it to a list. It'll check if the start volume and end volume are the same and if they're not, it'll fade to the end volume.
Private Sub SndCueGO(cue1, cue2)
Dim cues() = {cue1, cue2}
snd_num1 = cue1
Dim cuedata1 = snd_ds.Tables(0).Rows(cue1 - 1)
Dim cuedata2 = snd_ds.Tables(0).Rows(cue1 - 1)
If cue2 <> -1 Then
snd_num2 = cue2
cuedata2 = snd_ds.Tables(0).Rows(cue2 - 1)
End If
Dim data() = {cuedata1, cuedata2}
For i = 0 To 1
If cues(i) <> -1 Then
snd_delay(i) = data(i).Item("Delay")
snd_startvol(i) = safeNum(data(i).Item("Start_Vol."))
snd_file(i) = data(i).Item("File")
snd_in(i) = data(i).Item("Fade_In")
snd_out(i) = data(i).Item("Fade_Out")
snd_vol(i) = safeNum(data(i).Item("Vol."))
snd_hold(i) = data(i).Item("Hold")
snd_af(i) = If(data(i).Item("AF") = "", False, True)
player_list(i).URL = snd_file(i)
snd_current(i) = snd_startvol(i)
If snd_startvol(i) <> snd_vol(i) Then 'snd_startvol(i) and snd_vol(i) were the same in all my tests, so this should not run.
snd_next(i) = snd_vol(i)
Dim num_steps_up = snd_in(i) * snd_speed
Dim num_steps_down = snd_out(i) * snd_speed
Dim diff = snd_vol(i) - snd_startvol(i)
Dim small_step As Single
If diff > 0 Then
small_step = diff / num_steps_up
ElseIf diff < 0 Then
small_step = diff / num_steps_down
End If
snd_steps(i) = small_step
timer_snd_fade.Tag = 0
timer_snd_fade.Enabled = True
End If
timer_snd_master.Tag = 0 'resets the tag to 0
timer_snd_master.Enabled = True 'Starts timer
End If
Next
End Sub
Private Sub timer_snd_master_Tick(sender As Object, e As EventArgs) Handles timer_snd_master.Tick
If sender.Tag = snd_delay(0) Then
Player1.Ctlcontrols.play() 'This is the only play command in the program
Debug.Print("tag " & sender.Tag) 'These print after the delay
Debug.Print("delay " & snd_delay(0))
End If
sender.Tag += 1
End Sub
Inspect the:
AxWindowsMediaPlayer player1 = ...; // get the player from UI
IWMPSettings sett = player.settings;
sett.autoStart == ??
see the docs.
Probably it is set to true, as it's default value. Simply set it to false it the player will not play until Ctlcontrols.play() is invoked.
This program suppose to sort records(in arySort) in ascending order by last name(index 1 in aryTemp and aryTemp2) and place the result in the list box over the old, preloaded, unsorted records.
It sorts them strangely, I have to click multiple times the Ascending button to get the actual sort result that I suppose to get from clicking the button once.
Why doesn't it sort items with a single mouse click?
The source:
Public Class Form1
Dim FILE_NAME As String = "Students.txt"
Dim numberOfRecords As Integer 'total number of records
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
If System.IO.File.Exists(FILE_NAME) = True Then
Dim objReader As New System.IO.StreamReader(FILE_NAME)
Do While objReader.Peek() <> -1
lstBox.Items.Add(objReader.ReadLine)
numberOfRecords += 1
Loop
objReader.Close()
End If
End Sub
Private Sub btnAscending_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAscending.Click
'load all students into array
Dim arySort(numberOfRecords - 1) As String
Dim aryTemp() As String 'holds first record's last name
Dim aryTemp2() As String 'holds second record's last name
For i = 0 To numberOfRecords - 1
arySort(i) = lstBox.Items(i)
Next
Dim temp As String 'holds temporary record
Dim k As Integer
For i = 0 To arySort.Length - 2
aryTemp = Split(arySort(i), " ")
For k = i + 1 To arySort.Length - 1
aryTemp2 = Split(arySort(k), " ")
If aryTemp(1) < aryTemp2(1) Then
temp = arySort(k)
arySort(k) = arySort(i)
arySort(i) = temp
End If
Next
Next
lstBox.Items.Clear()
numberOfRecords = 0
For i = 0 To arySort.Length - 1
lstBox.Items.Add(arySort(i))
numberOfRecords += 1
Next
End Sub
End Class
If you just need to sort your list (as you say in the comment), don't implement your own sort mechanism but use the one of .NET:
' Define how we want to compare items '
Function compareByLastName(ByVal item1 As String, ByVal item2 As String) As Integer
Return String.Compare(item1.Split(" ")(1), item2.Split(" ")(1))
End Function
Private Sub btnAscending_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAscending.Click
' load all students into array '
Dim arySort(numberOfRecords - 1) As String
For i = 0 To numberOfRecords - 1
arySort(i) = lstBox.Items(i)
Next
' Use built-in .NET magic '
Array.Sort(arySort, AddressOf compareByLastName)
' Write the values back into your list box '
lstBox.Items.Clear()
numberOfRecords = 0
For i = 0 To arySort.Length - 1
lstBox.Items.Add(arySort(i))
numberOfRecords += 1
Next
End Sub
This uses the built-in quicksort algorithm of the .NET class library. Here's the documentation of the method we are using: Array.Sort(T(), Comparison(Of T)).
compare with my working bubble sort:
Public Sub BubbleSort(ByVal arr() As Integer)
Dim flag As Boolean = False
For i As Integer = 0 To arr.Length - 1
For j As Integer = 0 To arr.Length - 2 - i
If arr(j + 1) < arr(j) Then
flag = True
Dim temp As Integer = arr(j)
arr(j) = arr(j + 1)
arr(j + 1) = temp
End If
Next
If flag = False Then Return ' no swaps =>already sorted
Next
End Sub
I see a two major issues with your algorithm:
It's not bubble sort. Bubble sort swaps adjacent elements, i.e., it swaps i with i+1. You, on the other hand, swap some element i with the first j > i where name(i) < name(j). Maybe you should show us, in pseudo code, which algorithm you are actually trying to implement?
aryTemp contains element i and aryTemp2 contains some element j > i. Why do you swap the elements if aryTemp(1) < aryTemp2(1)? Isn't that already the correct order if you want your elements to be sorted ascending?