"Object reference not set to an instance of an object."

[Farhan_B]

im trying to get the insert to work but the problem i am facing is i keep getting this error

Can someone help please

thanks in advance my code is

Dim strsql As String = "Insert into cg_security_user (user_name,user_pwd) values (@field1,@field2) "

       Dim acscmd As New OleDb.OleDbCommand ' the oledbcommand

       With objcmd
           .Parameters.AddWithValue("@field1", txtuser.Text)
           .Parameters.AddWithValue("@field2", txtpass.Text)
        
       End With
       objcmd.ExecuteNonQuery()
       objcmd.Dispose()
       MsgBox("Saved")

[kingsonprisonic]

Because u declare acscmd as OleDb.OleDbCommand Object. But use objcmd in your code. Actually objcmd is not declared So you get the error.

[Farhan_B]

Imports System.Data.OleDb


Public Class Form2
    Dim objcmd As OleDbCommand
    
    Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'TODO: This line of code loads data into the 'DataSet.cg_security_user' table. You can move, or remove it, as needed.
        Me.Cg_security_userTableAdapter.Fill(Me.DataSet.cg_security_user)
        'TODO: This line of code loads data into the 'DataSet.cg_security_role' table. You can move, or remove it, as needed.
        Me.Cg_security_roleTableAdapter.Fill(Me.DataSet.cg_security_role)

    End Sub

  Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        connect()
    End Sub
    Sub connect()
        acsconn.ConnectionString = "Provider=Microsoft.jet.oledb.4.0;data source=C:\Users\HP Sajad\Documents\Visual Studio 2010\Projects\login1\login1\security.mdb"
        acsconn.Open()
        If acsconn.State = ConnectionState.Open Then
            MsgBox("Connected")

        End If
        acsconn.Close()


        Dim strsql As String = "Insert into cg_security_user (user_name,user_pwd) values (@field1,@field2) "

        Dim acscmd As New OleDb.OleDbCommand ' the oledbcommand

        With objcmd
            .Parameters.AddWithValue("@field1", txtuser.Text)
            .Parameters.AddWithValue("@field2", txtpass.Text)
         
        End With
        objcmd.ExecuteNonQuery()
        objcmd.Dispose()
        MsgBox("Saved")

    


    End Sub




  
    Private Sub txtcreatdate_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)

    End Sub
End Class

this is full script it has been declared on the top

[kingsonprisonic]

Too much error ..

Imports System.Data.OleDb


Public Class Form2
    Dim objcmd As OleDbCommand' You create a reference not an object. You have to declare like Dim  objcmd As New OleDbCommand. Use New Keyword for that
    
    Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'TODO: This line of code loads data into the 'DataSet.cg_security_user' table. You can move, or remove it, as needed.
        Me.Cg_security_userTableAdapter.Fill(Me.DataSet.cg_security_user)
        'TODO: This line of code loads data into the 'DataSet.cg_security_role' table. You can move, or remove it, as needed.
        Me.Cg_security_roleTableAdapter.Fill(Me.DataSet.cg_security_role)

    End Sub

  Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        connect()
    End Sub
    Sub connect()
        acsconn.ConnectionString = "Provider=Microsoft.jet.oledb.4.0;data source=C:\Users\HP Sajad\Documents\Visual Studio 2010\Projects\login1\login1\security.mdb"
        acsconn.Open()
        If acsconn.State = ConnectionState.Open Then
            MsgBox("Connected")

        End If
        acsconn.Close()


        Dim strsql As String = "Insert into cg_security_user (user_name,user_pwd) values (@field1,@field2) "'Here you declare the String but never assigned it to any command. Why???

        Dim acscmd As New OleDb.OleDbCommand ' Here you create an object of OleDb.OleDbCommand but where you use this??

        With objcmd ' You assign the Parameter but where you assign the command String??
            .Parameters.AddWithValue("@field1", txtuser.Text)
            .Parameters.AddWithValue("@field2", txtpass.Text)
         
        End With
        objcmd.ExecuteNonQuery()
        objcmd.Dispose()
        MsgBox("Saved")

    


    End Sub




  
    Private Sub txtcreatdate_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)

    End Sub
End Class

Now the clear code

Imports System.Data.OleDb


Public Class Form2
    Dim objcmd As OleDbCommand
    
    Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'TODO: This line of code loads data into the 'DataSet.cg_security_user' table. You can move, or remove it, as needed.
        Me.Cg_security_userTableAdapter.Fill(Me.DataSet.cg_security_user)
        'TODO: This line of code loads data into the 'DataSet.cg_security_role' table. You can move, or remove it, as needed.
        Me.Cg_security_roleTableAdapter.Fill(Me.DataSet.cg_security_role)

    End Sub

  Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        connect()
    End Sub
    Sub connect()
        acsconn.ConnectionString = "Provider=Microsoft.jet.oledb.4.0;data source=C:\Users\HP Sajad\Documents\Visual Studio 2010\Projects\login1\login1\security.mdb"
        acsconn.Open()
        If acsconn.State = ConnectionState.Open Then
            MsgBox("Connected")

        End If
        acsconn.Close()


        Dim strsql As String = "Insert into cg_security_user (user_name,user_pwd) values (@field1,@field2) "

       objcmd= New OleDb.OleDbCommand ' the oledbcommand
objcmd.CommandString=strsql 
        With objcmd
            .Parameters.AddWithValue("@field1", txtuser.Text)
            .Parameters.AddWithValue("@field2", txtpass.Text)
         
        End With
        objcmd.ExecuteNonQuery()
        objcmd.Dispose()
        MsgBox("Saved")
    End Sub

End Class

Now try this and see for any error.

[M.Waqas Aslam]

hello !

'please use new in this line 
 Dim objcmd As OleDbCommand
'----------------------------
'like this 
 Dim objcmd As new OleDbCommand

this will solve your prob .

Regards

[kingsonprisonic]

@wakasas..... Please see in my code i already use New into Sub Button1_Click event....

[M.Waqas Aslam]

well @king , there is not that much time i have to read code , i just saw the question , and i reply it , but as you said you also use new key word , but if you use simple way of helping and just keep your code to the point , then it is time saving and easy to understand ,as you write full code twice , that is not imp.

Stay blessed

M.Waqas Aslam