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+---- Thread: [.NET] Vb.net - access database (/showthread.php?tid=5864478)
Vb.net - access database - Uija - Jul 21, 2018
Hello everyone ,
at the beginning of my program you have to register. But what if the username already exists?I already wrote something , but It does nothing 😶 (when I click on the button it says nothing..)
Can someone say me what did I wrong ?
My code :
Imports System.Data.OleDb
Public Class Form1
Dim boolUsernameExists As Boolean = False
Private Sub FlatButton1_Click(sender As Object, e As EventArgs) Handles FlatButton1.Click
Dim strUsername As String = FlatTextBox1.Text
Try
If String.IsNullOrEmpty(strUsername) Then
Return
End If
Using dbConnection As OleDbConnection = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=|DataDirectory|\bin\Debug\Arbeiter.mdb")
dbConnection.Open()
Using dbCommand As OleDbCommand = New OleDbCommand("Select Count(*) FROM Arbeiter WHERE Forname LIKE?", dbConnection) ' "Arbeiter" is the name of the table and "Forname" is the username
dbCommand.Parameters.AddWithValue("@p1", strUsername)
Dim result As Integer = DirectCast(dbCommand.ExecuteScalar(), Integer)
If result > 0 Then
boolUsernameExists = True
MsgBox("Username already exists")
Else
End If
End Using
dbConnection.Close()
End Using
If boolUsernameExists Then
MsgBox("Username already exists")
Return
End If
Catch ex As Exception
End Try
End Sub
RE: Vb.net - access database - aneeshkollam5 - Jul 22, 2018
Using dbCommand As OleDbCommand = New OleDbCommand("Select * FROM Arbeiter WHERE Forname ='" & strUsername & "'", dbConnection)
Dim dr As OleDbDataReader = dbCommand.ExecuteReader()
If dr.HasRows Then
boolUsernameExists = True
MsgBox("Username already exists")
Else
End If
RE: Vb.net - access database - Uija - Jul 22, 2018
(Jul 22, 2018 02:28 AM)aneeshkollam5 Wrote: Using dbCommand As OleDbCommand = New OleDbCommand("Select * FROM Arbeiter WHERE Forname ='" & strUsername & "'", dbConnection)
Dim dr As OleDbDataReader = dbCommand.ExecuteReader()
If dr.HasRows Then
boolUsernameExists = True
MsgBox("Username already exists")
Else
End If
Thank you ! This works 🤗