利用VB在数据库SQL中存取图片

错误提示没有与可信任的数据库相连接 ，高手帮帮忙找出原因所在，我快要崩溃了，如果您有源代码请指教一个，万分感谢。
Imports
Imports System.Drawing.Printing
Imports System.Data.SqlClient


Public Class Form1
    Inherits System.Windows.Forms.Form
    Dim sqlCon As New SqlConnection("DATA SOURCE=202.118.12.169;INITIAL CATALOG=pubs;UID=SA;PWD=") 'DATA SOURCE后跟本机的ip或local,INITIAL CATALOG后为数据库的名字,UID后是sa,PWD后是密码

    Dim cn As SqlClient.SqlConnection

#Region " Windows Form Designer generated code "

    Public Sub New()
        MyBase.New()

        'This call is required by the Windows Form Designer.
        InitializeComponent()

        'Add any initialization after the InitializeComponent() call

    End Sub

    'Form overrides dispose to clean up the component list.
    'Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
    '    If disposing Then
    '        If Not (components Is Nothing) Then
    '            components.Dispose()
    '        End If
    '    End If
    '    MyBase.Dispose(disposing)
    'End Sub

    'Required by the Windows Form Designer
    Private component As

    'NOTE: The following procedure is required by the Windows Form Designer
    'It can be modified using the Windows Form Designer.
    'Do not modify it using the code editor.
    Friend WithEvents Label1 As System.Windows.Forms.Label
    Friend WithEvents Label2 As System.Windows.Forms.Label
    Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
    Friend WithEvents PictureBox1 As System.Windows.Forms.PictureBox
    Friend WithEvents Button1 As System.Windows.Forms.Button
    Friend WithEvents Button2 As System.Windows.Forms.Button
    Friend WithEvents OpenFileDialog1 As System.Windows.Forms.OpenFileDialog
    Friend WithEvents SqlConnection1 As System.Data.SqlClient.SqlConnection
    Friend WithEvents SqlCommand1 As System.Data.SqlClient.SqlCommand
    Friend WithEvents Button3 As System.Windows.Forms.Button
    Friend WithEvents Button4 As System.Windows.Forms.Button
    Friend WithEvents Button5 As System.Windows.Forms.Button
    <System.Diagnostics.DebuggerStepThrough()> Private Sub Initialize()
        Me.Label1 = New System.Windows.Forms.Label()
        Me.Label2 = New System.Windows.Forms.Label()
        Me.TextBox1 = New System.Windows.Forms.TextBox()
        Me.PictureBox1 = New System.Windows.Forms.PictureBox()
        Me.Button1 = New System.Windows.Forms.Button()
        Me.Button2 = New System.Windows.Forms.Button()
        Me.OpenFileDialog1 = New System.Windows.Forms.OpenFileDialog()
        Me.SqlConnection1 = New System.Data.SqlClient.SqlConnection()
        Me.SqlCommand1 = New System.Data.SqlClient.SqlCommand()
        Me.Button3 = New System.Windows.Forms.Button()
        Me.Button4 = New System.Windows.Forms.Button()
        Me.Button5 = New System.Windows.Forms.Button()
        Me.SuspendLayout()
        '
        'Label1
        '
        Me.Label1.Location = New System.Drawing.Point(15, 19)
        Me.Label1.Name = "Label1"
        Me.Label1.Size = New System.Drawing.Size(80, 24)
        Me.Label1.TabIndex = 0
        Me.Label1.Text = "姓名："
        '
        'Label2
        '
        Me.Label2.Location = New System.Drawing.Point(11, 64)
        Me.Label2.Name = "Label2"
        Me.Label2.Size = New System.Drawing.Size(80, 20)
        Me.Label2.TabIndex = 1
        Me.Label2.Text = "图片"
        '
        'TextBox1
        '
        Me.TextBox1.Location = New System.Drawing.Point(75, 16)
        Me.TextBox1.Name = "TextBox1"
        Me.TextBox1.Size = New System.Drawing.Size(173, 20)
        Me.TextBox1.TabIndex = 2
        Me.TextBox1.Text = ""
        '
        'PictureBox1
        '
        Me.PictureBox1.Location = New System.Drawing.Point(68, 48)
        Me.PictureBox1.Name = "PictureBox1"
        Me.PictureBox1.Size = New System.Drawing.Size(376, 222)
        Me.PictureBox1.TabIndex = 3
        Me.PictureBox1.TabStop = False
        '
        'Button1
        '
        Me.Button1.Location = New System.Drawing.Point(278, 13)
        Me.Button1.Name = "Button1"
        Me.Button1.Size = New System.Drawing.Size(96, 26)
        Me.Button1.TabIndex = 4
        Me.Button1.Text = "浏览图片…"
        '
        'Button2
        '
        Me.Button2.Location = New System.Drawing.Point(57, 277)
        Me.Button2.Name = "Button2"
        Me.Button2.Size = New System.Drawing.Size(100, 32)
        Me.Button2.TabIndex = 5
        Me.Button2.Text = "添加到数据库"
        '
        'SqlConnection1
        '
        Me.SqlConnection1.ConnectionString = "Data Source=.;Initial Catalog=mxh;User Id=sa;Password=;"
        '
        'SqlCommand1
        '
        Me. = "dbo.[sp_InsertPhoto]"
        Me. = System.
        Me.SqlCommand1.Connection = Me.SqlConnection1
        Me.SqlCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@RETURN_VALUE", _
            System.Data.SqlDbType.Int, 4, System.Data.ParameterDirection.ReturnValue, _
            False, CType(10, Byte), CType(0, Byte), "", System.Data.DataRowVersion.Current, Nothing))
        Me.SqlCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@name", _
            System.Data.SqlDbType.VarChar, 50))
        Me.SqlCommand1.Parameters.Add(New System.Data.SqlClient.SqlParameter("@image", _
            System.Data.SqlDbType.VarBinary, 2147483647))
        '
        'Button3
        '
        Me.Button3.Location = New System.Drawing.Point(265, 277)
        Me.Button3.Name = "Button3"
        Me.Button3.Size = New System.Drawing.Size(79, 32)
        Me.Button3.TabIndex = 6
        Me.Button3.Text = "显示记录"
        '
        'Button4
        '
        Me.Button4.Location = New System.Drawing.Point(362, 277)
        Me.Button4.Name = "Button4"
        Me.Button4.Size = New System.Drawing.Size(72, 32)
        Me.Button4.TabIndex = 7
        Me.Button4.Text = "退出"
        '
        'Button5
        '
        Me.Button5.Location = New System.Drawing.Point(167, 277)
        Me.Button5.Name = "Button5"
        Me.Button5.Size = New System.Drawing.Size(85, 32)
        Me.Button5.TabIndex = 8
        Me.Button5.Text = "删除该记录"
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.ClientSize = New System.Drawing.Size(491, 324)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.PictureBox1, _
            Me.Button5, Me.Button4, Me.Button3, Me.Button2, Me.Button1, Me.TextBox1, Me.Label1, Me.Label2})
        Me.Name = "Form1"
        Me.Text = "Form1"
        Me.ResumeLayout(False)

    End Sub

#End Region
    'Browse Button
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
      Handles Button1.Click
        'Display Picture File
        OpenFileDialog1.InitialDirectory = "d:\pic"
        OpenFileDialog1.DefaultExt = "gif"
        OpenFileDialog1.Filter = "Bmp Files(*.bmp)|*.bmp|Gif Files(*.gif)|*.gif|Jpg Files(*.jpg)|*.jpg"
        OpenFileDialog1.ShowDialog()
        PictureBox1.Image = Image.FromFile(OpenFileDialog1.FileName)
    End Sub

    'Add Button
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
      Handles Button2.Click
        ' To Insert Image
        Dim st As New FileStream(OpenFileDialog1.FileName, FileMode.Open, FileAccess.Read)
        Dim s As String = TextBox1.Text
        Dim mbr As BinaryReader = New BinaryReader(st)
        Dim buffer(st.Length) As Byte
        mbr.Read(buffer, 0, CInt(st.Length))
        st.Close()
        InsertImage(buffer, s)
    End Sub

    'Function For Inserting in the Procdeure in the Database
    Public Function InsertImage(ByRef buffer, ByVal str)
        cn = New SqlClient.SqlConnection(SqlConnection1.ConnectionString)
        cn.Open()
        Dim cmd As New SqlClient.SqlCommand("sp_InsertPhoto", cn)
         = CommandType.StoredProcedure
        cmd.Parameters.Add("@name", SqlDbType.VarChar).Value = TextBox1.Text
        cmd.Parameters.Add("@image", SqlDbType.Image).Value = buffer
        cmd.ExecuteNonQuery()
        MsgBox("Image inserted")
        cn.Close()
    End Function

    'Function to Display Image
    Private Sub ShowImage(ByVal s As String)
        cn = New SqlClient.SqlConnection(SqlConnection1.ConnectionString)
        cn.Open()
        Dim str As String = "SELECT photo FROM Photos WHERE name='" & s & "'"
        Dim cmd As New SqlClient.SqlCommand(str, cn)
        TextBox1.Text = s
        Dim b() As Byte
        b = cmd.ExecuteScalar()
        If (b.Length > 0) Then
            Dim stream As New MemoryStream(b, True)
            stream.Write(b, 0, b.Length)
            DrawToScale(New Bitmap(stream))
            stream.Close()
        End If
        cn.Close()
    End Sub

    'Function to Create Instance For the Image From the Buffer
    Private Sub DrawToScale(ByVal bmp As Image)
        PictureBox1.Image = New Bitmap(bmp)
    End Sub

    '显示处理
    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
      Handles Button3.Click
        Dim i As String = InputBox("请输入名字：")
        ShowImage(i)
    End Sub

    '退出处理
    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
      Handles Button4.Click
        Me.Dispose()
    End Sub

    '删除处理
    Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
      Handles Button5.Click
        cn = New SqlClient.SqlConnection(SqlConnection1.ConnectionString)
        cn.Open()
        Dim s As String = InputBox("请输入要删除的名字：")
        Dim cmd As New SqlClient.SqlCommand("delete from photos where name='" & s & "'", cn)
        cmd.ExecuteNonQuery()
        MsgBox("Image deleted")
        cn.Close()
    End Sub

  
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        If sqlCon.State = ConnectionState.Closed Then
            sqlCon.Open()
        End If
    End Sub
End Class