The input box is "not declared".
Not sure exactly why this happening and I can't figure it out.
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Do
f = InputBox("Inputs", "Enter The name Of the File.")
If f = Nothing Or f = "" Then
MessageBox.Show("Ooops!! No file name entered.")
Else
Exit Do
End If
Loop
End Sub
It appears that you didn't initialize the f variable:
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Do
Dim f As String = InputBox("Inputs", "Enter The name Of the File.")
...
Loop
End Sub
Have you initialized the form using InitializeComponent() in the constructor?
Other than that, this (more concise) code works as expected for me:
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Do
If Not String.IsNullOrEmpty(InputBox("Inputs", "Enter the name of the file.")) Then Exit Do
MessageBox.Show("Oops!! No file name entered.")
Loop
End Sub
I'd check your references. And turn Option Strict On in any case to highlight any type/declaration issues.
Related
I'm new to programming and I'm trying to figure out this simple question! The language is Visual Basic! The Question is below:
"Users of a computer program often like to enter numbers with commas inserted in the middle, such as "1,234,000,688". Most computer languages consider this format to be non numeric. Write a program that inputs a number containing no more than three commas, and produces a string containing the same number without the commas"
When I enter this number: 1,234,000,688 and hit Display in Visual Basic I get this error message --> Argument is out of range Exception was unhanded
I'm not exactly sure why this is happening because I'm within my strUserInput length.
My Code:
Public Class Form1
Private Sub btnDisplay_Click(sender As Object, e As EventArgs) Handles btnDisplay.Click
'Variable declarations
Dim strUserInput = txtUserInput.Text
Dim strOutputNumber1 As String
Dim strOutputNumber2 As String
Dim strOutputNumber3 As String
Dim strOutputNumber4 As String
' 1,234,000,688
strOutputNumber1 = strUserInput.Substring(0, 1)
strOutputNumber2 = strUserInput.Substring(2, 4)
strOutputNumber3 = strUserInput.Substring(5, 8)
strOutputNumber4 = strUserInput.Substring(9, 12)
lblDisplayNumber.Text = strOutputNumber1 & strOutputNumber2 & strOutputNumber3 & strOutputNumber4
End Sub
Private Sub btnExit_Click(sender As Object, e As EventArgs) Handles btnExit.Click
Me.Close()
End Sub
Private Sub btnClear_Click(sender As Object, e As EventArgs) Handles btnClear.Click
lblDisplayNumber.Text = String.Empty
txtUserInput.Text = String.Empty
End Sub
End Class
You're getting that exception because of the way you're using substring, the last one there starts at index 9 and extends 12 characters...that would be a 22 character number, and the text you have as input is probably much shorter. You don't need to make things overly complicated for yourself using substrings, all of the above code could be greatly condensed and cleaned up by simply using String.Replace like this:
Public Class Form1
Private Sub btnDisplay_Click(sender As Object, e As EventArgs) Handles btnDisplay.Click
lblDisplayNumber.Text = txtUserInput.Text.Replace(",", "")
End Sub
Private Sub btnExit_Click(sender As Object, e As EventArgs) Handles btnExit.Click
Me.Close()
End Sub
Private Sub btnClear_Click(sender As Object, e As EventArgs) Handles btnClear.Click
lblDisplayNumber.Text = String.Empty
txtUserInput.Text = String.Empty
End Sub
End Class
I create a form 'frmX' and i call it as a modal form :
res = frmX.ShowDialog()
This form has 3 buttons, Abort(3), Retry(4) and Ignore(5), but when the form opens, all the buttons on the first click return 2.
I don't know why this occurs--all of the buttons has their property DialogResult right.
*Private Sub btnIgnorar_Click(sender As Object, e As EventArgs) Handles btnIgnorar.Click
btnIgnorar.DialogResult = DialogResult.Ignore
End Sub
Private Sub btnAbortar_Click(sender As Object, e As EventArgs) Handles btnAbortar.Click
btnAbortar.DialogResult = DialogResult.Abort
End Sub
Private Sub btnReintentar_Click(sender As Object, e As EventArgs) Handles btnReintentar.Click
btnReintentar.DialogResult = DialogResult.Retry
End Sub*
Can someone help me?
Could do with seeing a bit more context, but the following should do what I think you want:
Private Sub btnIgnorar_Click(sender As Object, e As EventArgs) Handles btnIgnorar.Click
DialogResult = DialogResult.Ignore
Close
End Sub
This will close the dialog and return the associated result code to the caller. As to the original code, it seems a bit strange setting the values in the buttons click handlers?
The error comes from the fact that you set the DialogResult of the buttons. You must set the DialogResult of the form !
You actually have more than one option.
Option 1 : Set the Form.DialogResult
Private Sub btnIgnorar_Click(sender As Object, e As EventArgs) Handles btnIgnorar.Click
Me.DialogResult = DialogResult.Ignore
End Sub
Private Sub btnAbortar_Click(sender As Object, e As EventArgs) Handles btnAbortar.Click
Me.DialogResult = DialogResult.Abort
End Sub
Private Sub btnReintentar_Click(sender As Object, e As EventArgs) Handles btnReintentar.Click
Me.DialogResult = DialogResult.Retry
End Sub
Option 2 : Set the Button.DialogResult
Public Sub New()
InitializeComponents()
'Your init code here
'...
'By setting the buttons DialogResults, you don't even have to handle the click events
btnIgnorar.DialogResult = DialogResult.Ignore
btnAbortar.DialogResult = DialogResult.Abort
btnReintentar.DialogResult = DialogResult.Retry
End Sub
'However, if you need to do some stuff before closing the form, you can
Private Sub btnAbortar_Click(sender As Object, e As EventArgs) Handles btnAbortar.Click
'Do some stuff
'You don't need the following line, as it will be done implicitly
'Me.DialogResult = DialogResult.Abort
End Sub
I'm very frustrated trying to get my code to work.
I'm trying to have a selected item in a listbox removed also in the textbox.
Getting ready to remove text;
Removed the text;
But it's still in the textbox.
Here is my code
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
ListBox1.Items.Add(TextBox1.Text)
TextBox2.Text += TextBox1.Text & vbNewLine
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
ListBox1.Items.Remove(ListBox1.SelectedItem)
'
'//HOW TO REMOVE THE SELECTED TEXT IN THE LISTBOX ALSO REMOVED IN THE TEXTBOX2??
'
'
End Sub
Private Sub Form1_FormClosing(sender As Object, e As FormClosingEventArgs) Handles Me.FormClosing
Dim filenames As String = "C:\log\log.txt"
My.Computer.FileSystem.WriteAllText(filenames, TextBox2.Text, False)
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim filenames As String = "C:\log\log.txt"
If My.Computer.FileSystem.FileExists(filenames) Then
TextBox2.Text = My.Computer.FileSystem.ReadAllText(filenames)
Dim items()
items = TextBox2.Lines()
For Each item In items
ListBox1.Items.Add(item)
Next
End If
End Sub
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
Clipboard.SetText(ListBox1.SelectedItem)
End Sub
End Class
The worst part is that every time I try to look it up online, there are no errors until I click the button that says 'Value Cannot Be Null'
It happened every single time.
Please, before you mash the -1 button, at least tell me why. I'm new to this.
This should work for you
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
TextBox1.Text = TextBox1.Text.Replace(ListBox1.Items(ListBox1.SelectedIndex), Nothing)
ListBox1.Items.RemoveAt(ListBox1.SelectedIndex)
End Sub
End Class
when i try to show dialog of one of my forms it displays this error all other forms work perfectly i have tried to copy the code into another form happened the same
here is the error:
A first chance exception of type 'System.InvalidOperationException'
occurred in hyper market system.exe
Additional information: An error occurred creating the form. See
Exception.InnerException for details. The error is: Object reference
not set to an instance of an object.
If there is a handler for this exception, the program may be safely continued.
here is all my code
Public Class farm
Dim inifile As New IniFile(myfiles & "\system.ini")
Dim myfiles As String = My.Computer.FileSystem.SpecialDirectories.MyDocuments & "\HMsystem"
Private Sub Form2_Load(sender As Object, e As EventArgs) Handles MyBase.Load
End Sub
Private Sub TextBox1_TextChanged(sender As Object, e As EventArgs) Handles TextBox1.TextChanged
End Sub
Dim Count As Integer = 0
Dim total As Long = 0
Dim productnum As String = TextBox1.Text
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim productnum As String = TextBox1.Text
Dim num As String = TextBox2.Text
Dim itemname As String = inifile.GetString("productname", productnum, "غير موجود")
Dim price As String = inifile.GetString("productprice", productnum, "غير موجود")
ListView1.Items.Add(productnum)
ListView1.Items(Count).SubItems.Add(itemname)
ListView1.Items(Count).SubItems.Add(num)
ListView1.Items(Count).SubItems.Add(price)
total += price
Count += 1
Dim a As String = inifile.GetString("productquan", productnum, "0")
Dim itemquannow As String = inifile.GetString("productquan", productnum, "0")
If itemquannow <= 5 Then
Else
MsgBox("لم يبق الا 5 من هذا المنتج")
End If
inifile.WriteInteger("productquan", productnum, a - num)
MsgBox("تم الاضافة")
End Sub
Private Sub TextBox2_TextChanged(sender As Object, e As EventArgs) Handles TextBox2.TextChanged
End Sub
Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
Label4.Text = total & " السعر النهائي"
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
ListView1.Clear()
TextBox1.Clear()
TextBox2.Clear()
Count = 0
total = 0
MsgBox("تم الشراء بنجاح")
End Sub
Private Sub Label4_Click(sender As Object, e As EventArgs) Handles Label4.Click
End Sub
Private Sub ListView1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListView1.SelectedIndexChanged
End Sub
Private Sub Label3_Click(sender As Object, e As EventArgs) Handles Label3.Click
End Sub
Private Sub Label2_Click(sender As Object, e As EventArgs) Handles Label2.Click
End Sub
Private Sub Label1_Click(sender As Object, e As EventArgs) Handles Label1.Click
End Sub
End Class
When you get an error message like that, i.e. "An error occurred creating the form", it almost always means the same basic issue: you have an event handler that is being raised because of a property value set in the designer and that event handler assumes that the user has made that change after the form has been displayed. For instance, if you set the Text property of a TextBox in the designer then that's going to raise the TextChanged event. If you have handled that event then your event handler is going to be executed during the initialisation of the form, before it has been displayed to the user. If you assume that, for instance, an item is selected in a ComboBox then you're in trouble because there will be no such selection.
As the error message states, look at the InnerException, which will tell you exactly where the original exception was thrown. That will tell you which event handler is the issue and you can then look at the code in that method and determine what would cause an issue if the form had not yet been displayed. If in doubt, update your question with the code of that event handler and tell us where the exception was thrown, which the stack trace will tell you.
I created a simple program that reads and writes to an output file in the bin folder, it works almost perfect. btnRemove deletes the selected item in cboFriends(which is good). However, I also need btnRemove to delete text entered in the text box portion. How do i do this? I apologize in advance for the basicness of the question.
Public Class frmMain
Private Sub btnExit_Click(sender As Object, e As EventArgs) Handles btnExit.Click
Me.Close()
End Sub
Private Sub frmMain_FormClosing(sender As Object, e As FormClosingEventArgs) Handles Me.FormClosing
Dim outFile As IO.StreamWriter
outFile = IO.File.CreateText("MyFriends.txt")
For intIndex As Integer = 0 To cboFriends.Items.Count - 1
outFile.WriteLine(cboFriends.Items(intIndex))
Next intIndex
outFile.Close()
End Sub
Private Sub frmMain_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim inFile As IO.StreamReader
Dim strInfo As String
If IO.File.Exists("MyFriends.txt") Then
inFile = IO.File.OpenText("MyFriends.txt")
Do Until inFile.Peek = -1
strInfo = inFile.ReadLine
cboFriends.Items.Add(strInfo)
Loop
inFile.Close()
End If
End Sub
Private Sub btnAdd_Click(sender As Object, e As EventArgs) Handles btnAdd.Click
If cboFriends.Items.Contains(cboFriends.Text) Then
Else
cboFriends.Items.Add(cboFriends.Text())
End If
End Sub
Private Sub btnRemove_Click(sender As Object, e As EventArgs) Handles btnRemove.Click
cboFriends.Items.Remove(cboFriends.Text)
End Sub
End Class
It appears you are looking for the SelectedText property
To set it to a blank string, do the following
cboFriends.SelectedText = ""
cboFriends.SelectedText would work if the text was selected, but if i type "asdfjkl;" and then press [Remove] it does nothing.
Upon further digging cboFriends.Text = "" does the trick!