ＶＢ从ACCESS数据库中读取图片问题？哪位大侠帮解决一下。

[xiaobei0623]

Image1.Picture = LoadPicture(rs.Fields(0))
这条语句错了。我该如何写这条语句，谢谢。

[MMABing]

如果是用二进制数值写入的，就必须用二进制的方式读取出来呀。
二进制应该会吧

[xiaobei0623]

我的ＡＣＣＥＳＳ数据库中的数据类型是“超链接“

[xiaobei0623]

是把这个图片的地址作为FIELD（0）

[a11s]

用二进制来做(sql server似乎是image类型)
这样得到的数据流就是图象的数据流,至于如何才能转化成bmp....

vb.net有办法直接new bitmap from stream就ok了,但是vb6似乎就困难了,需要额外的sdk,比如intel的jpeg压缩.或者你写临时文件,然后再用picturebox加载(不是好办法的办法)

[FengLing7885]

数据类型问题，用超链接类型不行，用字符串！
LoadPicture(rs.Fields(0))读出来的是路径！不是以二进制的方式！

[饮水需思源]

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

[xiaobei0623]

那么怎样处理相对路径和绝对路径问题。就是图片的存放问题。以便提高程序的可移植性？？

[oyf888]

直接把图片的内容放入数据库，然后用二进制数据读入保存到文件中再显示即可。
Private Sub ReadFromDB()
Dim MediaTemp As String
Dim lngOffset As Long
Dim lngTotalSize As Long
Dim strChunk As String
Dim Title As String
On Error Resume Next

If Fa.MouseRow = 0 Then Exit Sub 'only use good rows
Title = Fa.TextMatrix(Fa.MouseRow, 1)
Set rs = db.OpenRecordset("SELECT tblMedia.Picture FROM tblMedia WHERE tblMedia.Title = '" & Title & "'", dbOpenSnapshot)
If rs.RecordCount = 0 Then
MsgBox "error retrieving object"
rs.Close
Set rs = Nothing
Exit Sub
End If


MediaTemp = App.Path & "\mdiatemp.tmp"

DataFile = 1
Open MediaTemp For Binary Access Write As DataFile

If Err.Number = 70 Then
MsgBox Err.Number & Err.Description
Err.Clear
rs.Close
Set rs = Nothing
Exit Sub
End If

lngTotalSize = rs!Picture.FieldSize
Chunks = lngTotalSize \ ChunkSize
Fragment = lngTotalSize Mod ChunkSize
'ReDim Chunk(Fragment)
ReDim Chunk(ChunkSize)
Chunk() = rs!Picture.GetChunk(lngOffset, ChunkSize)
Put DataFile, , Chunk()
lngOffset = lngOffset + ChunkSize
Do While lngOffset < lngTotalSize
Chunk() = rs!Picture.GetChunk(lngOffset, ChunkSize)
Put DataFile, , Chunk()
lngOffset = lngOffset + ChunkSize
Loop
Close DataFile

FileName = MediaTemp

End Sub


Private Sub FileName_Change()
SaveToDB.Enabled = FileName <> ""
If FileName = "" Then Exit Sub

Image1.Picture = LoadPicture(FileName)
Image1.Visible = True

End Sub

[yuanlulaomao]

就放相对路径进去就可以了~~~~

Image1.Picture = LoadPicture(FileName)