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Hello ! why i can't catch event keydown in a form that contain a datagridview. i have use KeyPreview= true in form load. but i still can't get any keydown value after pressing key. please give me some advise
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See here[^].
Me, I'm dishonest. And a dishonest man you can always trust to be dishonest.
Honestly. It's the honest ones you want to watch out for...
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I tried and works fine for me.
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Hi all,
I have an issue with a datagrid in VB 2008 Express. I have loaded an Excel file into a datagrid as a preview; now I want to insert the datagrid content into a table in an Oracle DB (tha table have the same fields of the excel file). How ca I do it? I have tried with the following code but doesn't work 
Using connection As New OleDbConnection(connectionString)
Dim adapter As New OleDbDataAdapter()
adapter.InsertCommand = New OleDbCommand(queryString, connection)
Dim builder As OleDbCommandBuilder = New OleDbCommandBuilder(adapter)
connection.Open()
adapter.Fill(data)
adapter.Update(data, tableName)
Return data
End Using
When VB try to execute this command
adapter.Fill(data)
it crash with vshost error. If I Delete this row the functon works, but I haven't the data into the table.
Is there anyone can help me?
Many thanks
Filippo
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What is the error message?
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"vshost.exe has stopped working" and the application crash
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Hi tried also to cicle into the rows/cols into the Datase with the following instruction
Dim iRow As Integer
Dim iCols As Integer
Dim sriga As String
For iRow = 0 To dgvPreview.RowCount
For iCols = 0 To dgvPreview.ColumnCount
If Len(sriga) = 0 Then
sriga = dgvPreview.Rows(iRow).Cells(iCols).Value.ToString
Else
sriga = sriga & ", " & dgvPreview.Rows(iRow).Cells(iCols).Value.ToString
End If
Next
TextBox2.Text = TextBox2.Text & vbCrLf & sriga
TextBox2.Refresh()
sriga = ""
Next
But the finel result is the same The Vb crash with the same vshost error
Please Help me! I'm going mad!
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Try the following:
For iRow = 0 To dgvPreview.RowCount - 1
For iCols = 0 To dgvPreview.ColumnCount - 1
(Note the additional "- 1" at the end of the lines)
Maybe it is also helpful for your further devolpments to use try-catch-blocks, to handle exceptions. Normally the Exception itself contains several useful information, which could help you to identify the error's position and circumstances.
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Well, first of all, I don't think you're understanding how ADO.Net works.
I suggest starting here: Overview of ADO.NET[^].
The InsertCommand that you are creating is used to run a SQL Insert...or in other words to insert a record into a database. And, the InsertCommand is only used when running an Update where records are marked as added or if you say InsertCommand.ExecuteNonQuery().
If you are trying to fill a table, you need to change the way you are setting up the table. I suggest looking at: OleDBDataAdapter Class[^]
You want to change it to provide a SelectCommand. Generally, you do this like:
newDataAdapter = New OleDb.OleDbDataAdapter(sql, connectionString)
newDataAdapter.Fill(ProjectDS, "ProjectInfo")
I would say you clearly haven't looked at how to use ADO.NET and you need to start there.
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One more thing...you need to make sure to close your connection before returning. It's bad practice to keep it open. I also hope you're creating the DataTable in your function because if it's a global variable, then why are you returning it? And if it's not accessible outside whatever class you're using, why are you making it a global variable?
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Hi dear!,
I am trying to create a ruler for my project. The ruler is from right to left. I want to add an autowidth propert, which should automatically set the width of ruler when the form is resized.
at design time it works but at run time it give me error.
Following is the Ruler's code and it give error when I add it to an application and run it.
Public Class nytRuler
Private Sub nytRuler_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles Me.Paint
Dim g As Graphics = e.Graphics
Dim p As Point = New Point(0, 0)
Dim s As Size = New Size(Me.Width, Me.Height)
Dim curRec As Rectangle = Me.ClientRectangle()
g.DrawRectangle(Pens.Black, curRec)
'Converting Pixels to Twips
Dim dpmm As Single = g.DpiX / 25.4F
Dim ptoTwip As Single = (curRec.Width * 15)
'Twips to Inches
Dim twipToInches As Single = CSng(ptoTwip / 1440)
Dim b As Single = curRec.Width
'Draw Numders 1 2 3 etc.
For a As Single = 0 To twipToInches
g.DrawString(a, New Font("Arial", 10), Brushes.Black, b, 10)
b = b - 96 '288 192 96
Next
b = curRec.Width
'Dim ptomm As Integer = Me.Width / dpmm
'Draw Lines between inches, and long line every 5th
Dim y As Single = 10.0F
Dim z As Integer = 0
For x As Single = b To 0 Step -9.6
g.DrawLine(Pens.Black, x, 0, x, y)
z += 1
If z = 5 Then
y = 15
z = 0
Else
y = 10
End If
Next
End Sub
Private wd As Boolean
Public Property autowidth() As Boolean
Get
Return wd
End Get
Set(ByVal value As Boolean)
If value Then
Me.Width = ParentForm.Width
End If
wd = value
Me.Invalidate()
End Set
End Property
End Class
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nyt1972 wrote: at design time it works but at run time it give me error.
Maybe you should tell us what the error is, so we can maybe narrow down the problem. It does help us who haven't developed our telepathy yet.
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I have copied and pasted your code into a new forms application and it generates a ruler when the project is run in Debug and in Release.
So without knowing your problem/error, can't help!
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You are tying to create a control for ruler.
if you'r using control in your form it will work like same as run time.
I think you should use graphics to set in your control and do't use the paint method to crate image in the control.
If you can think then I Can.
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Thanks for reply dear,
The problem is that When I build the Ruler and add it to a form then I set the rulers autowidth property to True and run the Application it shows me the following error.
System.InvalidOperationException was unhandled
Message="An error occurred creating the form. See Exception.InnerException for details. The error is: Object reference not set to an instance of an object."
Source="WindowsApplication1"
StackTrace:
at WindowsApplication1.My.MyProject.MyForms.Create__Instance__[T](T Instance) in 17d14f5c-a337-4978-8281-53493378c1071.vb:line 190
at WindowsApplication1.My.MyProject.MyForms.get_Form1()
at WindowsApplication1.My.MyApplication.OnCreateMainForm() in C:\Documents and Settings\Administrator\Local Settings\Application Data\Temporary Projects\WindowsApplication1\My Project\Application.Designer.vb:line 35
at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.OnRun()
at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.DoApplicationModel()
at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.Run(String[] commandLine)
at WindowsApplication1.My.MyApplication.Main(String[] Args) in 17d14f5c-a337-4978-8281-53493378c1071.vb:line 81
at System.AppDomain._nExecuteAssembly(Assembly assembly, String[] args)
at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()
InnerException: System.NullReferenceException
Message="Object reference not set to an instance of an object."
Source="WindowsApplication1"
StackTrace:
at WindowsApplication1.nytRuler.set_autowidth(Boolean value) in C:\Documents and Settings\Administrator\Local Settings\Application Data\Temporary Projects\WindowsApplication1\nytRuler.vb:line 45
at WindowsApplication1.Form1.InitializeComponent() in C:\Documents and Settings\Administrator\Local Settings\Application Data\Temporary Projects\WindowsApplication1\Form1.Designer.vb:line 31
at WindowsApplication1.Form1..ctor() in C:\Documents and Settings\Administrator\Local Settings\Application Data\Temporary Projects\WindowsApplication1\Form1.Designer.vb:line 53
InnerException:
Please help, I will be thankful.
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Pls pls pls help me, I am getting mad.
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nytRuler is a class, I want to create a dll file and then Insert that ruler to an application where it causes this error when I set the ruler's autowidth property to true and run the application.
hope this will make u understand.
Please help.
Thanks in Advance.
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Hi
I have DatePicker and the Maxdate is set to today:
I am struggling with the MinDate.
I need to set the Mindate to the 1st of 3 Months back(Keep in mind that the current month will be 3rd Month).
Ex.1
For instance if we work it out as today the MinDate has to be: 01 January 2010
Ex.2
if today is the 16th of April 2010 the min date has to be: 01 Feb 2010
I hope someone can help me with this as I am really struggling with this calculation
Thank you in advanced
modified on Tuesday, March 30, 2010 5:39 AM
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I think this is what you want
minDate = DateAdd(DateInterval.Month, -2, Today)
minDate = DateAdd(DateInterval.Day, (Today.Day - 1) * -1, Today)
Steve Jowett
-------------------------
Real programmers don't comment their code. If it was hard to write, it should be hard to read.
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Thank you Steven, but if I work it from todays day it should be 01/01/2010 but the result your code gives is 3/1/2010.
I do appreciate your effort in helping.I'll try to work with this code and try to change it.
Thank you so much
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Thank you so much Steven
I have changed the second line of code and replaced today with mindate and its working perfect.
Im just wondering now what would happen if this month has 31 days and 3 months back has only 30.
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Member 4420534 wrote: Im just wondering now what would happen if this month has 31 days and 3 months back has only 30
Either reset your system clock to an appropriate date (not forgetting Feburary only has 28 days or 29 on Leap years).
Define a DateTime varable and use the DateSerial function to populate it with your test date, then use the testing dateTime variable instead of the current system date, to test your code.
Steve Jowett
-------------------------
Real programmers don't comment their code. If it was hard to write, it should be hard to read.
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Can anyone tell me how to resize an external application window from within a vb.net form? I know how to start and external application using process.start but now i need to know how to set its size when it starts.
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Take a look at Pinvoke - SetWindowPos[^]
Tarakeshwar Reddy
There are two kinds of people, those who do the work and those who take the credit. Try to be in the first group; there is less competition there. - Indira Gandhi
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Thanks for the help I think that will do just what I want
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