VB6之在MDB数据库中存取图片

'使用流对象保存和显示图片 

'打开vb6,新建工程。

'添加两个按钮,一个image控件

'注意:Access中的photo字段类型为OLE对象.

'SqlServer中的photo字段类型为Image

'** 引用 Microsoft ActiveX Data Objects 2.5 Library 及以上版本

‘2.5版本以下不支持Stream对象

Dim iConcstr As String

Dim iConc As ADODB.Connection

 

'保存文件到数据库中

Sub s_SaveFile()

    Dim iStm As ADODB.Stream

    Dim iRe As ADODB.Recordset

    Dim iConcstr As String

    '读取文件到内容

    Set iStm = New ADODB.Stream

    With iStm

        .Type = adTypeBinary   '二进制模式

        .Open

        .LoadFromFile App.Path + "\test.jpg"

    End With

   

    '打开保存文件的表

    Set iRe = New ADODB.Recordset

    With iRe

        .Open "select * from img", iConc, 1, 3

        .AddNew         '新增一条记录

        .Fields("photo") = iStm.Read

        .Update

    End With

   

   '完成后关闭对象

    iRe.Close

    iStm.Close

End Sub

Sub s_ReadFile()

    Dim iStm As ADODB.Stream

    Dim iRe As ADODB.Recordset

    '打开表

Set iRe = New ADODB.Recordset

‘得到最新添加的纪录

    iRe.Open "select top 1 * from img order by id desc", iConc, adOpenKeyset, adLockReadOnly

    '保存到文件

    Set iStm = New ADODB.Stream

    With iStm

        .Mode = adModeReadWrite

        .Type = adTypeBinary

        .Open

        .Write iRe("photo")

‘这里注意了,如果当前目录下存在test1.jpg,会报一个文件写入失败的错误.

        .SaveToFile App.Path & "\test1.jpg"

    End With

   

    Image1.Picture = LoadPicture(App.Path & "\test1.jpg")

   '关闭对象

    iRe.Close

    iStm.Close

End Sub

 

Private Sub Command1_Click()

Call s_ReadFile

End Sub

Private Sub Command2_Click()

Call s_SaveFile

End Sub

Private Sub Form_Load()

    '数据库连接字符串

    iConcstr = "Provider=Microsoft.Jet.OLEDB.4.0;Persist Security Info=False" & _

        ";Data Source=F:\csdn_vb\database\保存图片\access图片\img.mdb"

‘下面的语句是连接sqlserver数据库的.

    ‘iConcstr = "Provider=SQLOLEDB.1;Persist Security Info=True;" & _

‘ "User ID=sa;Password=;Initial Catalog=test;Data Source=yang"

 

   Set iConc = New ADODB.Connection

   iConc.Open iConcstr

End Sub

 

Private Sub Form_Unload(Cancel As Integer)

iConc.Close

Set iConc = Nothing

End Sub