vb.net 当用户登录程序时，如何从 Access 数据库中检索数据？
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How to retrieve data from Access Database, when user are login to the program?
提问by user3496755
to all my senior. I'm doing an assignment about Music Sales System.
给我所有的前辈。我正在做一个关于音乐销售系统的作业。
When the system begin will start a form "Login.vb", it allow the user to login with Staff ID and Password. After that, if login successful it will show the name of the staff in a textbox.
当系统开始时会启动一个表格“Login.vb”，它允许用户使用员工 ID 和密码登录。之后，如果登录成功，它将在文本框中显示员工姓名。
Could any senior help me or teach me how to retrieve the name when the staff login to the system?
有哪位前辈能帮我或者教教我员工登录系统时如何找回姓名吗？
Furthermore, I also like to retrieve picture from Access Database, hope can get some help from here.
此外，我也喜欢从 Access 数据库中检索图片，希望能从这里得到一些帮助。
I'm using Jet.Oledb.4.0.
我正在使用 Jet.Oledb.4.0。
Thank You.
谢谢你。
Below is my Login.vb code
下面是我的 Login.vb 代码
Private Sub btnLogin_Click(sender As Object, e As EventArgs) Handles btnLogin.Click
Private Sub btnLogin_Click(sender As Object, e As EventArgs) 处理 btnLogin.Click
Dim Connection As New Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Music_Sales_Database.mdb;")
Dim Command As New Data.OleDb.OleDbCommand("SELECT [Staff_ID] FROM [Staff] WHERE [Staff_IDField] = Staff_ID AND [PasswordField] = Password", Connection)
Dim StaffIDParam As New Data.OleDb.OleDbParameter("Staff_ID", Me.txtStaff_ID.Text)
Dim PasswordParam As New Data.OleDb.OleDbParameter("Password", Me.txtPassword.Text)
Command.Parameters.Add(StaffIDParam)
Command.Parameters.Add(PasswordParam)
Command.Connection.Open()
Dim Reader As Data.OleDb.OleDbDataReader = Command.ExecuteReader()
If txtStaff_ID.Text = "" Then
MessageBox.Show("Staff ID and Password cannot be empty, please try again.", "Login Failed", MessageBoxButtons.OK, MessageBoxIcon.Asterisk)
ElseIf txtPassword.Text = "" Then
MessageBox.Show("Staff ID and Password cannot be empty, please try again.", "Login Failed", MessageBoxButtons.OK, MessageBoxIcon.Asterisk)
ElseIf Reader.HasRows Then
MessageBox.Show("You are authenticated.", "Login Successful", MessageBoxButtons.OK, MessageBoxIcon.Asterisk)
MyPlayer.SoundLocation = path & LogOnSound
MyPlayer.Play()
txtPassword.Text = ""
Me.Hide()
Main_System.Show()
Else
MessageBox.Show("Invalid Staff ID or Password, please try again.", "Login Failed", MessageBoxButtons.OK, MessageBoxIcon.Error)
txtPassword.Text = ""
txtPassword.Focus()
End If
Command.Connection.Close()
End Sub
******BELOW is the program that Im coding, but still coding.......coz Im still new in VB.....hope can get some help
** ****BELOW 是我正在编码的程序，但仍在编码......因为我还是 VB 新手......希望能得到一些帮助
Dim Connection As New OleDb.OleDbConnection
Dim Command As OleDb.OleDbCommand
Dim Reader As OleDb.OleDbDataReader
Dim DBPath As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Music_Sales_Database.mdb;"
Dim Image() As Byte
Private Sub RetrieveStaffInformation()
Connection.ConnectionString = DBPath
Connection.Open()
Command = Connection.CreateCommand
Command.CommandText = "SELECT Staff.* FROM Staff"
Reader = Command.ExecuteReader
Image = CType(Reader(0), Byte())
Dim MS As New System.IO.MemoryStream(Image)
Dim bmImage As New Bitmap(MS)
picStaff.Image = bmImage
picStaff.Refresh()
End Sub
回答by King of kings
I give you code for sql.change it to access
我给你 sql.change 的代码来访问
Dim com As SqlCommand
com = New SqlCommand("select uname,pwd from logg where uname='" & TextBox1.Text & "' and pwd='" & TextBox2.Text & "'", conn)
Dim da As New SqlDataAdapter(com)
Dim ds As New Data.DataSet
da.Fill(ds)
If ds.Tables(0).Rows.Count = 1 Then
MsgBox("Successfully logged in")
Label1.Text = ds.Tables(0).Rows(0)("uname")
End If
