vb.net 中如何将图片保存到SQL数据库

如题，把图片保存到SQL数据库当中，有人推荐使用“保存路径”的方法。但是具体怎么做？？？
如果想要直接保存到数据库当中，又该怎么做？？？
 
可以的话给出具体的步骤和代码，以及注释
新人提问，答案越详细越好。

追问：具体怎么做？？

答案：（注意在看的时候,也没有必要全部看,首先看骨架,然后在看图片怎么保存到数据库中的就行了,另外,这里涉及到了fileSream流,主要是用来读取数据,与此相关的还有网络方面的NetworkStream,呵呵,还有很多)   
微软的SQL SERVER数据库的Image、text等字段都属于二进制的大对象。这些对象的存取和其他轻型对象略有不同。比如，我们打开一个数据表的时候，普通类型的字段都可以看见，而Image类型的字段却不行，只能通过编程的方法来读取。这篇资料就是介绍怎样用vb.NET来向sql server数据库中存放图片，怎样从数据库中取出图片浏览
这个例程用到了 sql server自带的northwind数据库，其中employees（职员）数据表有一个字段“photo”，是用来存放照片的，里面有9条记录，我费了半天力气，想去看看那9个人图片，就是看不见。现在猜测，这些人的photo根本就是空的。所以，我决定添加一些新的记录。
在这个例程里，我实现了一个简单的WinForm程序，这个程序通过点击“Open”按钮选择一个图片文件（bmp或jpg），并显示在图形控件PictureBox中。通过“Save”按钮存入数据库。点击“View”CheckBox可以切换到浏览状态，观看存入数据库的图片。
    微软.NET Framework的System.IO命名空间下给我们提供了一个FileStream文件流类。我们可以使用这个文件流对二进制大对象轻松进行读写。由于对二进制大对象使用的流操作，所以对于任何文件都具有通用性。读写文本文件也可以这么做。
步骤：
1、 先来看一下northwind数据库中employees表结构

2、 知道.net连接sql server的方法嘛，不知道的话，看看我写的“ado.net中的connection对象”吧。读懂下面这几句没问题吧：
Dim conn as new sqlconnection(“server=localhost;database=northwind;Integrated Security=true;”
Dim sqlcomm As New SqlCommand
sqlcomm.Connection = conn 
sqlcomm.CommandText = "INSERT INTO employees (lastname,firstname,photo) VALUES (@lastname,@firstname,@photo)" 
Dim prm1 As New SqlParameter("@lastname", txtLN.Text)
Dim prm2 As New SqlParameter("@firstname", txtFN.Text)
Dim prm3 As New SqlParameter("@photo", SqlDbType.VarBinary, Int(fs.Length), _ ParameterDirection.Input, False, 0, 0, "", DataRowVersion.Current, Data)
sqlcomm.Parameters.Add(prm1)
sqlcomm.Parameters.Add(prm2)
sqlcomm.Parameters.Add(prm3)
3、新建一个windows应用程序窗体
4、 声明类级的变量。找到设计期产生的代码部分，把下面的语句加到变量声明后面。什么？不知道变量声明在哪儿?不会吧！
Private fs As FileStream
Private ds As DataSet
Private conn As New SqlConnection("server=localhost;database=northwind;integrated security=true;")
Private currentpos As Integer = 9
5、 开始写代码了。首先是form_load
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
btnOpen.Enabled = True
btnSave.Enabled = True
btnBack.Enabled = False
btnForward.Enabled = False
End Sub
6、 open按钮的点击事件代码：
Private Sub openbtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnOpen.Click
Dim Opendlg As New OpenFileDialog
Opendlg.Title = "Select a picture file"
Opendlg.Filter = "(*.bmp)|*bmp|(*.jpg)|*.jpg"
Opendlg.ShowDialog()
lblPath.Text = Opendlg.FileName.ToString()
fs = New FileStream(Opendlg.FileName.ToString(), FileMode.Open, FileAccess.Read)
PictureBox1.Image = Image.FromFile(Opendlg.FileName.ToString())
End Sub
7、 save按钮的点击事件代码
Private Sub savebtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click
Dim sqlcomm As New SqlCommand
sqlcomm.CommandText = "INSERT INTO employees (lastname,firstname,photo) VALUES (@lastname,@firstname,@photo)"
sqlcomm.Connection = conn
Dim Data(fs.Length) As Byte
fs.Read(Data, 0, Int(fs.Length))
Dim prm1 As New SqlParameter("@lastname", txtLN.Text)
Dim prm2 As New SqlParameter("@firstname", txtFN.Text)
Dim prm3 As New SqlParameter("@photo", SqlDbType.VarBinary, Int(fs.Length), ParameterDirection.Input, False, 0, 0, "", DataRowVersion.Current, Data)
sqlcomm.Parameters.Add(prm1)
sqlcomm.Parameters.Add(prm2)
sqlcomm.Parameters.Add(prm3)
Try
conn.Open()
sqlcomm.ExecuteNonQuery() '执行插入语句
conn.Close()
fs.Close()
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub
8、 选择view状态的事件代码
Private Sub CheckBox1_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged
If CheckBox1.Checked = True Then
btnOpen.Enabled = False
btnSave.Enabled = False
btnBack.Enabled = True
btnForward.Enabled = True
currentpos = 9
Dim sqlcomm As New SqlCommand
sqlcomm.CommandText = "SELECT employeeId, photo FROM employees ORDER BY employeeId"
sqlcomm.Connection = conn
Dim da As New SqlDataAdapter(sqlcomm)
Try
conn.Open()
ds = New DataSet
da.Fill(ds, "employees")
conn.Close()
Catch sqlEx As SqlException
MsgBox(sqlEx.Message)
End Try
Dim data() As Byte = ds.Tables("employees").Rows(9)("photo")
Dim stmphoto As New MemoryStream(data)
PictureBox1.Image = Image.FromStream(stmphoto)
Else
btnOpen.Enabled = True
btnSave.Enabled = True
btnBack.Enabled = False
btnForward.Enabled = False
End If
End Sub
9、 “>>”按钮点击事件代码
Private Sub forward_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnForward.Click
If currentpos = ds.Tables("employees").Rows.Count - 1 Then
Return
Else
currentpos += 1
Dim data() As Byte
data = ds.Tables("employees").Rows(currentpos)("photo")
Dim stmphoto As New MemoryStream(data)
PictureBox1.Image = Image.FromStream(stmphoto)
End If
End Sub
10、 “<<”按钮点击事件代码
Private Sub back_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnBack.Click
If currentpos = 9 Then
Return
Else
currentpos -= 1
End If
Dim Data() As Byte
Data = ds.Tables("employees").Rows(currentpos)("photo")
Dim stmPhoto As New MemoryStream(Data)
PictureBox1.Image = Image.FromStream(stmPhoto)
End Sub
（我是摘录的 http://blog.chinaunix.net/u1/36875/showart_283820.html）
都是只保存路径的，把图片放到一个专用的文件夹下，读取的时候，从路径得图片

#Region "二进制文件的存储函数"
 
    Public Function BinaryToFile(ByRef TableRowColItem As Object, ByVal FileName As String) As Boolean
        Dim data As Byte() = TableRowColItem
        Dim myfilestream As New System.IO.FileStream(FileName, IO.FileMode.Create)
        myfilestream.Write(data, 0, data.Length)
        myfilestream.Close()
        Return True
    End Function
    Public Function BinaryToImage(ByRef TableRowColItem As Object, ByRef image As Image) As Boolean
        Dim data As Byte() = TableRowColItem
        Dim imgStream As New System.IO.MemoryStream '(data)
        imgStream.Write(data, 0, data.Length)
        image = System.Drawing.Image.FromStream(imgStream)
        imgStream.Close()
        imgStream.Dispose()
        Return True
    End Function

    Public Function BinaryFromFile(ByVal FileName As String, ByRef TableRowColItem As Object) As Boolean
        Using myfilestream As New FileStream(FileName, FileMode.Open, FileAccess.Read)
            Dim data() As Byte
            ReDim data(myfilestream.Length - 1)
            myfilestream.Read(data, 0, myfilestream.Length)
            myfilestream.Close()
            TableRowColItem = data
        End Using

        Return True
    End Function
    Public Function BinaryFromImage(ByRef Image As Image, ByRef TableRowColItem As Object) As Boolean

        Dim imgStream As New MemoryStream
        Dim b As New Bitmap(Image)
        b.Save(imgStream, System.Drawing.Imaging.ImageFormat.Jpeg)
        Dim data As Byte() = imgStream.G

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