Question

我有一个FileUpload fileupload2控件和一个图像框控件image1。现在我想保存浏览图像，并在浏览路径时将其显示在图像框上。我正在编写如下代码。

该代码中的问题是什么以及当我浏览路径时如何在图像框中显示它？

Protected Sub btnsave_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnsave.Click
    Connection()

    Dim cmd As New SqlCommand
    cmd.Connection = cn
    cmd.CommandText = "INSERT INTO Personal_info (image_id,pic)VALUES (@image_id,@pic)"

    cmd.Parameters.Add("@image_id", SqlDbType.VarChar, 200)
    cmd.Parameters.Add("@pic", SqlDbType.Image, 200)

    cmd.Parameters("@image_id").Value = txtid.Text
    cmd.Parameters("@pic").Value = FileUpload2.FileBytes

    Dim i = -1

    i = cmd.ExecuteNonQuery

    If i = -1 Then
        lblMessage.ForeColor = Drawing.Color.Red
        lblMessage.Text = "Fail to Save"
        'MsgBox("Fail", MsgBoxStyle.OkOnly, "Error")
    Else
        lblMessage.ForeColor = Drawing.Color.Green
        lblMessage.Text = "Success to Save"
    End If
End Sub

Answer 1

要在图像框中显示imange，您需要提供imange路径或网址。你无法直接从数据库中读取它。

一种方法是

从数据库中检索imange
将图像保存在服务器中

将图像服务器路径传递给图像框

'1. retrieve the imange from the database
Dim cmd As New SqlCommand
cmd.Connection = cn
cmd.CommandText = "SELECT pic FROM Personal_info  WHERE image_id=@image_id;"

cmd.Parameters.Add("@image_id", image_id)

Dim rd As SqlDataReader = cmd.ExecuteReader
Dim MyData() As Byte
If rd.Read Then
    If rd("pic").ToString <> Nothing Then
        MyData = rd("pic")
    End If

End If

'2. save the image in the server
Dim oFileStream As New System.IO.FileStream(System.AppDomain.CurrentDomain.BaseDirectory & "image\image.jpg", System.IO.FileMode.Create, IO.FileAccess.ReadWrite)
oFileStream.Write(MyData, 0, MyData.Length)
oFileStream.Close()

'3. pass the image box the image server path
image1.ImageUrl = "~/image/image.jpg"

如何使用Asp.Net通过VB.Net在SQL Server 2008R2中保存和检索图像

1 个答案: