I am making a simple calculator and it's saying InvalidCastException was unhandled when I try to debug it, here's the code, please tell me whats wrong with it: (and yes I have renamed the textboxes to addequals etc...
Public Class Form1
Private Sub WebBrowser1_DocumentCompleted(ByVal sender As System.Object, ByVal e As System.Windows.Forms.WebBrowserDocumentCompletedEventArgs)
End Sub
[code].....
I have some trouble in SMS gateway project using VB.Net (VS 2010)while programme was running, I found error "InvalidCastException was Unhandled", then my programme cannot continue. below I copy the code of the programme :
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Option Explicit On
Public Class MessageReceiver
Private TPMessageTime As String
[code]....
I'm implementing following code in VS2010:
If xl.cells(1, contacolonna).Borders(Excel.XlBordersIndex.xlEdgeRight).LineStyle <> Excel.XlLineStyle.xlContinuous Then
MsgBox("hello")
End If
or following
[code]....
but in both cases VS returns following error:"InvalidCastException was unhandled Overload resolution failed because no Public '=' can be called with these arguments:'Public Shared Operator =(a As String, b As String) As Boolean':Argument matching parameter 'a' cannot convert from '__ComObject' to 'String'. "
I have just upgraded to Microsoft Visual Basis 2010 Express (Running on Vista and Microsoft Office Excel 2007). The last time I used VB was about 5 years ago and was v5.0 I am trying to do the very simple action of opening a spreadsheet using VB and reading in cell values into two text boxes (I am using an example posted on the web to ensure my approach is correct). The run fails at the point:
[Code]...
Dim CustID As String = txtSrchCustID.Text
Dim FirstName As String = txtNewCustFName.Text
Dim SecondName As String = txtNewCustSName.Text
If CustID And FirstName And SecondName = "" Then
MsgBox("Please enter a term to search by")
EndIf
This returns "Conversion from string "" to type 'Long' is not valid." I was wondering what the error is and how it's possible to fix it? The other questions that I've looked at were mostly to do with variables assigned incorrect types, but I think that isn't the issue. It occurs when all of the variables are empty.
OK, this is going better, now im stuck in the mud again, i am trying to get a form to print,this works now, however i would like to enable a few frames with text boxes for a few seconds to allow the printer to print the text in black instead of gray. he error i am getting is this, as the timer disables:" Unable to cast object of type System.Windows.Forms.Timer' to type 'System.Windows.Forms.ToolStripMenuItem'. "
Public
Sub
Print_Renamed_Click(ByVal
[code].....
Private Sub gvDesignGVnote_CellClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles gvDesignGVnote.CellClick
If e.RowIndex < 0 Then[code]......
I am trying to get a 3rd party activex control which works in VB6 to work in Visual Studio 2005. Using the same exact code I am receiving an InvalidCastException error. Specified cast is not valid.
The code is as follows: AxQIChartControl1.DataTable =
"A-Filler"
AxQIChartControl1.Columns =
"Weight"
AxQIChartControl1.ChartType = 2
[Code]...
below is my piece of code where I click on "Edit button" then retrieve the data from access database so that I edit them on a form.
This is what I get when I click on edit: InvalidCastException was unhandled and highlights the line below The UserID contain Alphanumeric characters.
'check for the selected item in list
If lvUsersList.SelectedItems.Count > 0 Then
If Me.lvUsersList.SelectedItems.Count > 0 Then
[Code].....
I use this code to populate combobox1&2:
'Main form on load events
Private Sub frm_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
[Code]....
I'm a beginner to Visual Basic. In here I want to recreate a piggy bank which tells me how much money do I have. I created a function but the program tells me :
[Code]...
why I got the following (InvalidCastException was unhandled) on the following code and how can I solve the problem.
LabelPB.Text = P - Total.Text 'Conversion from string "" to type 'Double' is not valid
I am trying to catch the System.InvalidCastException error. If I put a number into the calculator the program runs ok. If the calculate button is pressed with nothing in the text boxes I get the casting error Conversion from string "" to type 'Decimal' is not valid. I understand why I am getting the error. I don't know what to do about it. I want the program to dump null data and go back to waiting for input from the user.
Private Sub btnCalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculate.Click
Dim FedTaxRate = 0.13 ' constants for taxes and work week
[code].....
I use code such as this to clear out the values in several text boxes: Private Sub RibbonButtonInsert_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles RibbonButtonInsert.Click
[Code]...
Because the date picker control did not clear out like the other controls did, I tried:
DatePickerDateOfBirth.Value = ""
but it does not clear out. Instead, I get an "InvalidCastException". show me what coding I need to properly clear out the value in this data picker?
I have used the Gridview_PageIndexChanging event in asp.net.i have used the code like this:
gridFileDetails.PageIndex = e.NewPageIndex
During the run time when i clicked the next page,it generates an error:
An exception of type 'System.InvalidCastException' occurred in FFK.DLL but was not handled in user
code
Additional information: Unable to cast
object of type
'System.Web.UI.WebControls.ContentPlaceHolder'
to type
'System.Web.UI.WebControls.GridViewRow'.
in the RowCommand event,I have used the following RowCommand event:
Protected Sub gridFileDetails_RowCommand(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewCommandEventArgs) Handles gridFileDetails.RowCommand
Dim row As GridViewRow = CType(CType(e.CommandSource, Control).NamingContainer, GridViewRow)
[code]....
Error is Simple Application -- Error Type (A first chance exception of type 'System.InvalidCastException' occurred in Microsoft.VisualBasic.dll)
View 3 RepliesI have this issue with casting....is there anyway i could pass an integer into a label...this is what i have done so far but i am getting this error "A first chance exception of type 'System.InvalidCastException' occurred in Microsoft.VisualBasic.dll"
Dim firstNumber As Integer
Dim secondNumber As Integer
Dim solution As Integer
[CODE].........................
ok so i viewed some other question that are ruffly the same and i am still confused, here is the stacktrace
at Game3.My.MyProject.MyForms.Create__Instance__[T](T Instance) in 17d14f5c-a337-4978-8281-53493378c1071.vb:line 190
at Game3.My.MyProject.MyForms.get_Character_Creator()
at Game3.My.MyApplication.OnCreateMainForm() in C:UsersMasonDocumentsVisual Studio 2010ProjectsGame3Game3My ProjectApplication.Designer.vb:line 35
[Code]...
also, where is game3.my.myproject, obviously its a line of code but what is it in.
I am puzzled by why it does not retrieve the data and keep saying i have a error "InvalidCastException", i am currently doing these in compact framework and is totally new to it, i searched around looking for a way to get data into a listview base on what little i know about java . these are my creation of table and inserting during formload
[Code]...
In my project I'm trying to get the caption property of serial ports available on computer. But when I run this code below I get "A first chance exception of type 'System.InvalidCastException' occurred in Microsoft.VisualBasic.dll" exception. I tried putting "Option Strict On" and then I'm getting build error saying it disallows Late binding.
[Code]...
i am in project of medical billing.i am on LogIn form in vb.but i have Erro - "InvalidOperationException was unhandle " and while i was run program it didn't say which line i had error.
here is my code.
Imports System.Data.OleDb
Public Class login
Inherits System.Windows.Forms.Form
[code].....
I have made a tic tac toe board and when i go to debug the application i get a "NullReferenceException was unhandled".
this happens diring this part of the code:
Dim x As Integer = Val(index.Chars(0))
Dim conn As New OleDb.OleDbConnection
Dim ds As New DataSet
Dim da As OleDb.OleDbDataAdapter
Dim sql As String
[code]....
The above code stops running at the point of the da.fill line with the error that the specified table does not exist.In my limited knowledge so far to me it looks like the operators table exists as it showing in the Solution Explorer.
Trying to port old code from VB6.
Public CHandles() As Long
Public SHandles() As Long
Public rerrors() As Long
[code]....
Generates a SafeArrayTypeMismatchException was unhandled. Specified Array was not of the expected type error.I assume it means the SHandles, rerrors, and CHandles arrays but not sure.
The exception is thrown in a defined class when trying to call a Sub procedure.
The main Form1:
Imports TeenyStudent.Student
Public Class Form1
Private students As Array = Array.CreateInstance( _
GetType(Student), 20)
[code]...
I'm getting a "TypeLoadException was unhandled" error. The description says Could not load type 'dnUtilities.OtherFunctions' from assembly 'dnUtilities, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'.
So i've got a class library project. I've built that into a dll and am referencing it in a project in another solution. The name is "dnUtilities" and i've stored a lot of subs and functions inside it. I just got this error when i added a new module and tried calling a sub from it. I've got no idea why this error is happening since all the other functions from the other modules work. Besides modules i've also got a usercontrol in the dll. The framework of the dll and my calling project are both 3.5.
I was testing out an application that I created which then I recieved an error as said in this topic title. The application that I am making is one where it requires 2 form GUIs, my main one is called frmConferenceRegistrationSystem (the first picture) and my secondary one is called frmConferenceOptions (The second picture) and what they are supposed to do overall is total up the cost of registering for a conference that is selected in frmConferenceOptions and the error that I am recieving is within the ElseIf statements in the frmConferenceOptions form (third picture and first section of code) And also here is the rest of my code for both of my form GUIs at the bottom of this topic
If ltbList.SelectedItem(IntrotoECommerce) And ckbConferenceRegistration896.CheckState = CheckState.Checked Then
My frmConferenceRegistrationSystem Code:
Public Class frmConferenceRegistrationSystem
[code]....
i have a probleam with my coding.The error which i got is olehDBexeception was unhandled.In my coding here i am developing function use to subtract number in database based on user input.I dont how to solve this error? I also highlight the line cause an error and also i attach picture of the probleam.
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'open db connection'
[code]....
[code] I'm basically trying to see if a record already exists. My problem is when I run this I get a "ArgumentNullException was unhandled" error It occurs on the line "dbAdapter.Fill(output)" in the sub.
View 5 RepliesAll, I am trying to have my program self terminate, (the equivalent to clicking the X close program). I want my 2010 program to run and then stop.
I have tried the me.close() but I get the error:ObjectDisposedException was unhandled
The code works fine, and I do get the file created, but.... I get the error.
Here is my short
Public Class Form1
Public Sub New()
Dim buffer1 As String
[Code]......