Search Results

Search found 3 results on 1 pages for 'user127147'.

Page 1/1 | 1 

  • VB.NET invalid cast exception

    - by user127147
    Hi there, I have a simple application to store address details and edit them. I have been away from VB for a few years now and need to refreash my knowledge while working to a tight deadline. I have a general Sub responsible for displaying a form where user can add contact details (by pressing button add) and edit them (by pressing button edit). This sub is stored in a class Contact. The way it is supposed to work is that there is a list with all the contacts and when new contact is added a new entry is displayed. If user wants to edit given entry he or she selects it and presses edit button Public Sub Display() Dim C As New Contact C.Cont = InputBox("Enter a title for this contact.") C.Fname = frmAddCont.txtFName.Text C.Surname = frmAddCont.txtSName.Text C.Address = frmAddCont.txtAddress.Text frmStart.lstContact.Items.Add(C.Cont.ToString) End Sub I call it from the form responsible for adding new contacts by Dim C As New Contact C.Display() and it works just fine. However when I try to do something similar using the edit button I get errors - "Unable to cast object of type 'System.String' to type 'AddressBook.Contact'." Dim C As Contact If lstContact.SelectedItem IsNot Nothing Then C = lstContact.SelectedItem() C.Display() End If I think it may be something simple however I wasn't able to fix it and given short time I have I decided to ask for help here. Thank you

    Read the article

  • Invalid cast exception

    - by user127147
    I have a simple application to store address details and edit them. I have been away from VB for a few years now and need to refreash my knowledge while working to a tight deadline. I have a general Sub responsible for displaying a form where user can add contact details (by pressing button add) and edit them (by pressing button edit). This sub is stored in a class Contact. The way it is supposed to work is that there is a list with all the contacts and when new contact is added a new entry is displayed. If user wants to edit given entry he or she selects it and presses edit button Public Sub Display() Dim C As New Contact C.Cont = InputBox("Enter a title for this contact.") C.Fname = frmAddCont.txtFName.Text C.Surname = frmAddCont.txtSName.Text C.Address = frmAddCont.txtAddress.Text frmStart.lstContact.Items.Add(C.Cont.ToString) End Sub I call it from the form responsible for adding new contacts by Dim C As New Contact C.Display() and it works just fine. However when I try to do something similar using the edit button I get errors - "Unable to cast object of type 'System.String' to type 'AddressBook.Contact'." Dim C As Contact If lstContact.SelectedItem IsNot Nothing Then C = lstContact.SelectedItem() C.Display() End If I think it may be something simple however I wasn't able to fix it and given short time I have I decided to ask for help here. I have updated my class with advice from other members and here is the final version (there are some problems however). When I click on the edit button it displays only the input box for the title of the contact and actually adds another entry in the list with previous data for first name, second name etc. Public Class Contact Public Contact As String Public Fname As String Public Surname As String Public Address As String Private myCont As String Public Property Cont() Get Return myCont End Get Set(ByVal value) myCont = Value End Set End Property Public Overrides Function ToString() As String Return Me.Cont End Function Sub NewContact() FName = frmAddCont.txtFName.ToString frmStart.lstContact.Items.Add(FName) frmAddCont.Hide() End Sub Public Sub Display() Dim C As New Contact C.Cont = InputBox("Enter a title for this contact.") C.Fname = frmAddCont.txtFName.Text C.Surname = frmAddCont.txtSName.Text C.Address = frmAddCont.txtAddress.Text 'frmStart.lstContact.Items.Add(C.Cont.ToString) frmStart.lstContact.Items.Add(C) End Sub End Class

    Read the article

  • VB.NET editing existing that with a form

    - by user127147
    Hi there, I have a simple questions that puzzles me. I need a little bit of refreashment with VB as I have been away for a while. I have a form that adds new contacts. New contacts are added by pressing an appropriate button and they appear as an entry in the list on the form. I try now to add an edit button that will edit existing entries. User will select a given entry on the list and press edit button and will be presented with an appropriate form (AddContFrm). Right now it simply adds another entry with the same title. Logic is handled in a class called Contact.vb Here is my code. Public Class Contact Public Contact As String Public Title As String Public Fname As String Public Surname As String Public Address As String Private myCont As String Public Property Cont() Get Return myCont End Get Set(ByVal value) myCont = Value End Set End Property Public Overrides Function ToString() As String Return Me.Cont End Function Sub NewContact() FName = frmAddCont.txtFName.ToString frmStart.lstContact.Items.Add(FName) frmAddCont.Hide() End Sub Public Sub Display() Dim C As New Contact 'C.Cont = InputBox("Enter a title for this contact.") C.Cont = frmAddCont.txtTitle.Text C.Fname = frmAddCont.txtFName.Text C.Surname = frmAddCont.txtSName.Text C.Address = frmAddCont.txtAddress.Text 'frmStart.lstContact.Items.Add(C.Cont.ToString) frmStart.lstContact.Items.Add(C) End Sub End Class AddContFrm Public Class frmAddCont Public Class ControlObject Dim Title As String Dim FName As String Dim SName As String Dim Address As String Dim TelephoneNumber As Integer Dim emailAddress As String Dim Website As String Dim Photograph As String End Class Private Sub btnConfirmAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnConfirmAdd.Click Dim C As New Contact C.Display() Me.Hide() End Sub Private Sub frmAddCont_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load End Sub End Class and frmStart.vb Public Class frmStart Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click frmAddCont.Show() End Sub Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDel.Click Dim DelCont As Contact DelCont = Me.lstContact.SelectedItem() lstContact.Items.Remove(DelCont) End Sub Private Sub lstContact_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lstContact.SelectedIndexChanged End Sub Private Sub btnEdit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEdit.Click Dim C As Contact If lstContact.SelectedItem IsNot Nothing Then C = DirectCast(lstContact.SelectedItem, Contact) C.Display() End If End Sub End Class

    Read the article

1