Question

Private Sub btnLogin_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnLogin.Click

    ' Check if username or password is empty
    If txtPassword.Text = "" Or txtUsername.Text = "" Then
        MessageBox.Show("Please complete the required fields..", "Authentication Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
    Else
        ' Both fields was supply
        ' Check if user exist in database
        ' Connect to DB
        Dim conn As New System.Data.OleDb.OleDbConnection()
        conn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source = C:\Users\AMD\Desktop\sem 8 2013\fyp\vb\test last\test\fingerprint.accdb"



        Try
            'conn.Open()
            'MsgBox("Susscess")

            Dim sql As String = "SELECT * FROM admintable WHERE username='" & txtUsername.Text & "' AND password = '" & txtPassword.Text & "'"
            Dim sqlCom As New System.Data.OleDb.OleDbCommand(sql)

            'Open Database Connection
            sqlCom.Connection = conn
            conn.Open()

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

            If sqlRead.Read() Then

                '<retrieve fingerprint attachment from accdb>

            Else
                ' If user enter wrong username and password combination
                ' Throw an error message
                MessageBox.Show("Username and Password do not match..", "Authentication Failure", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)

                'Clear all fields
                txtPassword.Text = ""
                txtUsername.Text = ""

                'Focus on Username field
                txtUsername.Focus()
            End If

        Catch ex As Exception
            MessageBox.Show("Failed to connect to Database..", "Database Connection Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
        End Try

    End If
End Sub

这是我开发的编码。在我想要的应用程序中，在用户连续输入正确的用户名和密码后，可以检索存储在accdb中的指纹模板，以便进行验证。

有人可以帮助我，我对visual basic和sql连接的了解有限。

即时通讯使用数字角色设备获取指纹模板，我使用一键式SDK进行验证。

Answer 1

使用FileStream方法在byte（）中读取/存储数据库然后获取文件扩展名以正确地将其存储回它的扩展名中...

Answer 2

使用FileStream，您应该能够读取和写入您想要的任何文件。这是一个很好的例子，可以帮助您入门。

http://www.codeproject.com/Articles/32216/How-to-store-and-fetch-binary-data-into-a-file-str

如何使用vb 2010检索在Access中存储指纹模板（fpt）的附件？

2 个答案: