combobox

[Xiao_1]

in combobox how do can i select the user as student not other

e.g. if the user is student not Manager

Private Sub loginform_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

    Dim conn As New System.Data.OleDb.OleDbConnection()
    conn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\temp\Database1.accdb"

    Try

        Dim sqlcmd As String = "SELECT * FROM tbl_datain"
        Dim sqlCom As New System.Data.OleDb.OleDbCommand(sqlcmd)

        sqlCom.Connection = conn
        conn.Open()

        Dim sqlRead As System.Data.OleDb.OleDbDataReader = sqlCom.ExecuteReader()

        While sqlRead.Read()

            cbinfo.Items.Add(sqlRead("Personl").ToString)

        End While
        conn.Close()

    Catch ex As Exception

    End Try

End Sub

Private Sub cbinfo_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cbinfo.SelectedIndexChanged

    Dim conn As New System.Data.OleDb.OleDbConnection()
    conn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\temp\Database1.accdb"

    Try

        Dim sqlcmd As String = "SELECT * FROM tbl_datain WHERE Personl ='" & cbinfo.Text & "'"
        Dim sqlCom As New System.Data.OleDb.OleDbCommand(sqlcmd)

        sqlCom.Connection = conn
        conn.Open()

        Dim sqlRead As System.Data.OleDb.OleDbDataReader = sqlCom.ExecuteReader("Personl")

        While sqlRead.Read()


            txtname.Text = sqlRead.ToString("UserID")
            txtpass.Text = sqlRead.ToString("PassWord")

            cbinfo.Text = ""
            txtname.Text = ""

            cbinfo.Focus()

            MessageBox.Show("Wong student")


        End While
        conn.Close()

    Catch ex As Exception

    End Try
End Sub

[Santanu.Das]

Thinkless codification.
I do here some modification.
Your codes should be

Try
        Dim sqlcmd As String = "SELECT Count(*) FROM tbl_datain WHERE Personl ='" & cbinfo.Items(cbinfo.SelectedIndex) & "' " & _
        "And UserID ='" & txtname.Text & "' And PassWord ='" & txtpass.Text & "'"
        Dim sqlCom As New System.Data.OleDb.OleDbCommand(sqlcmd)
        sqlCom.Connection = conn
        conn.Open()
        Dim Result As Integer = sqlCom.ExeculeScalar()
        sqlCom.Dispose()
        conn.Close()

        if Result>0 then 
            'Do Here your process to save the attendence
            'of that student.

            MessageBox.Show("Present")

        Else
            MessageBox.Show("Wrong Input")
        End If

    Catch ex As Exception
    End Try

[Xiao_1]

the sqlCom.ExeculeScalar() 
have Error (Value of type 'System.Data.OleDb.OleDbDataReader' cannot be converted to 'Integer'.)    

[Xiao_1]

i have change to reader but dose not work at all

[Santanu.Das]

Remove the parenthesis from sqlCom.ExeculeScalar().
write it as sqlCom.ExeculeScalar.

[Minimalist]

Maybe check the spelling first?

sqlCMD.ExecuteScalar()

[Xiao_1]

*****Remove the parenthesis from sqlCom.ExeculeScalar().
write it as sqlCom.ExeculeScalar.*****

(no diffene)

[Minimalist]

It is .Execute with a t not .Execule