vb.net 存取数据库中的图片 (转)[@more@]

   以MS自带的Northwnd为例,其中有个表是Categories,有四个四段,其中有一个是Image类型的Picture字段.我们首先添加一张bmp图片到最后一行的Picture中,然后在读出来显示到Image中.

  添加一个DataAdapter1,用向导设置联接数据库为Northwnd,SQL语句为 [Category ID], [Category Name], Description, Picture FROM Categories.生成一个数据集为dataset1. 然后添加两个按钮分别表示写图片到数据库和读数据库,还有一个Image控件用于显示图片.

添加以下代码

 Private Sub Form1_Load(ByVal sender As System., ByVal e As System.EventArgs) Handles MyBase.Load

  SqlDataAdapter1.Fill(DataSet11)  End Sub

'从数据库读取图片暂时为monkey.bmp,然后加载到image控件里面. 

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles LoadPicFrom.Click  Try  Dim data As Byte() = DataSet11.Tables(0).Rows(7).Item(3)  Dim myfilestream As New System.IO.FileStream(Application.StartupPath & "monkey.bmp", IO.FileMode.Create)  myfilestream.Write(data, 0, data.Length)  myfilestream.Close()  PictureBox1.Image = New Bitmap(Application.StartupPath & "monkey.bmp")  Catch  End Try  End Sub

  '把C:6.bmp写入库中,你可以改为自己的图片.  Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles InsertPicToDb.Click  Dim myfilestream As New System.IO.FileStream("c:6.bmp", IO.FileMode.Open)  Dim data() As Byte  ReDim data(myfilestream.Length - 1)  myfilestream.Read(data, 0, myfilestream.Length)  myfilestream.Close()  DataSet11.Tables(0).Rows(7).Item(3) = data  SqlDataAdapter1.Update(DataSet11.GetChanges())  End Sub

 

 

来自 “ ITPUB博客 ” ，链接：http://blog.itpub.net/10748419/viewspace-1008982/，如需转载，请注明出处，否则将追究法律责任。