If you are using Visual Basic 2010 Express, you may see the error message above when you try to connect to a database. An easy way to fix this problem (but not the only way) is to use the Browse button in the Add Connection dialog box shown below, navigate to the DATA directory for SQL Server on your hard drive (see the location near the bottom of page 2 of this document), and select the particular database.mdf file.
20/04/2013
13/04/2013
VB.Net code for preventing duplicate entry in a ComboBox? Vb.Net code for beginners
Sometime when we are entering list of items and list of departments in a combobox and when the list which we are entering is longer then there is chances that some of the items we entered in list box may be duplicate or we can say a double entry of same items may be made. So now the question arises how to to prevent such entries at the time of making it. We can prevent such entry with this vb.net code
Private Sub BtnAddDep_Click(ByVal sender As System.Object,ByVal e As System.EventArgs) Handles BtnAddDep.Click
'Add department text property to ComboBox
listing
Dim FBoolean As Boolean = False
Dim IndInteger As
Integer = 0
Do Until FBoolean = True Or IndInteger =
DepComboBox.Items.Count
If DepComboBox.Text.Trim.ToUpper =
DepComboBox.Items(IndInteger).ToString.Trim.ToUpper
Then
FBoolean = True
Else
'Add 1 to index value
IndInteger += 1
End If
Loop 'Loop back and try again
'Now decide whether to add item or not
If FBoolean = False And
DepComboBox.Text.Trim
<> String.Empty Then
DepComboBox.Items.Add(DepComboBox.Text.Trim)
Else
MessageBox.Show("Duplicate or Invalid Department
Name", "Duplicate Data
Error", MessageBoxButtons.OK,
MessageBoxIcon.Exclamation)
DepComboBox.Focus()
DepComboBox.SelectAll()
End If
End Sub
Labels:
VB.Net
04/04/2013
What would cause DSL light to be on and internet light to be off? DSL on & internet Light off.
Binatone DT845W modem
During last September 2012 , I have bought a Broadband ADSL + wifi modem of Binatone compnay. The model no of my modem is Binatone DT845W and got it configured with BSNL Broad band connection. For two three days, it worked very fine but after that frequently its internet light got off sometime due to sudden power failure or sometimes without any reason. I got fed up with as I several times called BSNL people, they come and check their phone line and broadband setting and all the times they found everything fine but even then my modem internet light is not On, I did many R&D on my modem like when I repeatedly make power supply switch on-off, on-off it get working some times not.
How to make user id and password case sensitive ? VB.Net Code for beginners
After developing a software we try many things to make the software security proof and in that process we can try to make the user id and password case sensitive. for doing this these are the VB.Net code which I used in my program and it is working fine.
Imports System.Data.OleDb
Imports System.IO
Public Class
FrmLogin
Inherits
System.Windows.Forms.Form
Dim cn As New
OleDbConnection
Dim cmd As New
OleDb.OleDbCommand
Public
LoginSucceeded As Boolean
Dim Counter
As Integer
Dim bm As BindingManagerBase
Private Sub FrmLogin_Load(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
cn.ConnectionString = Moduledatasource
cn.Open()
LoginSucceeded = False
End Sub
Private Sub BtnOk_Click(ByVal
sender As System.Object, ByVal e As
System.EventArgs) Handles BtnOk.Click
Try
If
Counter = 8 Then
MsgBox("You
have exceeded the number of attempts")
Frmsplash.Close()
Me.Close()
Exit
Sub
End
If
If
TxtUserId.Text = "" Or TxtPassword.Text = ""
Then
MsgBox("You
must enter a user name and password.", _
vbOKOnly + vbInformation)
TxtUserId.Focus()
else
FrmMainMDI.Show()
Me.Hide()
Me.log()
Else
Dim
CmdER As New
OleDbCommand
Dim
MyReader As OleDb.OleDbDataReader
CmdER.Connection = cn
CmdER.CommandText = "Select * from UserAccount where UserId = '"
& TxtUserId.Text & " 'and UserPassword
= '" & TxtPassword.Text
& "'"
MyReader = CmdER.ExecuteReader
If
MyReader.Read() Then
'to
make the User Id and Password case snsitive
If
TxtPassword.Text <> MyReader("UserPassword").ToString
Or TxtUserId.Text <> MyReader("UserId").ToString Then
MessageBox.Show(" User ID and Password is case sensitive. Login
Denied ", " Error! ",
MessageBoxButtons.OK, MessageBoxIcon.Error)
TxtPassword.Text = ""
TxtPassword.Focus()
Else
TxtUserAccount.Text =
MyReader("AccountType")
If TxtUserAccount.Text = "A"
Then
FrmMainMDI.Show()
Me.Hide()
FrmMainMDI.DataBackupToolStripMenuItem.Enabled = True
Me.log()
Else
FrmMainMDI.Show()
Me.Hide()
FrmMainMDI.UtilityToolStripMenuItem.Enabled = False
FrmMainMDI.PrintToolStripMenuItem.Enabled = False
FrmMainMDI.ReportToolStripMenuItem.Enabled = False
Me.log()
End If
End
If
Else
MsgBox("Your user ID or Password is wrong")
TxtPassword.Text = ""
TxtUserId.Text = ""
TxtUserId.Focus()
End
If
LoginSucceeded = True
End
If
Catch
ex As Exception
Dim
MessageString As String
= "Report this error to the system
administrator: " & ControlChars.NewLine & ex.Message
Dim
TitleString As String
= "Employee Master Details Data Load
Failed"
MessageBox.Show(MessageString,
TitleString, MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try
End Sub
The above code is to check the user id case sensitivity and also type of user like admin or normal. Please comment your view.
Labels:
VB.Net
03/04/2013
How to restrict number of digits after decimal? VB.Net code for beginners!
Restricting the numbers of digit after decimal is very small code but it has very important role in coding for any program specially related in mathematical calculation and also in financial programming. Suppose one wants to divide 5 by 9 the correct answer will .55555555555555........ and if he wants to restrict the 2 or 4 digits after decimal then the answer will be .55 or .5555.
To achieve this result the VB.Net code will be " Math.Round(result, number of digits)"
Dim percent, row, counter As Double
percent = val(txtNo1.text)
counter = val(txtNo2.text)
row = counter / percent
Label12.Text = Math.Round(row, 2)
The above code will restrict the 2 digits after decimal and if one wants to increase the number of digits after decimal just change the 2 to any integer number.
Labels:
VB.Net
Subscribe to:
Posts (Atom)