我为提示输入 .jpeg 文件的过程编写了代码,将该文件转换为 Byte 数组,并使用 Append chunk 方法将 Byte Array 保存到表中。另一个过程使用 GetChunk 方法从表中检索图片图像,将数据转换为文件并在图片框中显示该文件。
现在,我的问题是如何将图片框中显示的图像保存到数据库中,以便我可以执行以下操作:添加/更新等。我做了这样的事情:
Private Sub CmdSave_Click()
if(cmbRNO=" ") then
sql = "INSERT INTO STUDENT_RECORD_DATABASE(ROLLNO,PICS)"
sql = sql + "VALUES(" & RNo & ","& picture1.picture &")"
Set RES = CON.Execute(sql)
Else
sql = "UPDATE STUDENT_RECORD_DATABASE SET "
sql = sql + "ROLLNO= " & Val(CmbRNO) & ","
sql = sql + "PICS=" & Picture1.Picture & " "
sql = sql + "WHERE ROLLNO= " & Val(CmbRNO) & ""
Set RES = CON.Execute(sql)
End If
End Sub
<code for appendchunk method>
Public Sub Command1_Click()
Dim PictBmp As String
Dim ByteData() As Byte 'Byte array for Blob data.
Dim SourceFile As Integer
' Open the BlobTable table.
strSQL = "Select ID, DOC from LOB_TABLE WHERE ID = 1"
Set Rs = New ADODB.Recordset
Rs.CursorType = adOpenKeyset
Rs.LockType = adLockOptimistic
Rs.Open strSQL, Cn
' Retrieve the picture and update the record.
CommonDialog1.Filter = "(*.jpeg)|*.jpeg"
CommonDialog1.ShowOpen
PictBmp = CommonDialog1.FileName
' Save Picture image to the table column.
SourceFile = FreeFile
Open PictBmp For Binary Access Read As SourceFile
FileLength = LOF(SourceFile) ' Get the length of the file.
If FileLength = 0 Then
Close SourceFile
MsgBox PictBmp & " empty or not found."
Exit Sub
Else
Numblocks = FileLength / BlockSize
LeftOver = FileLength Mod BlockSize
ReDim ByteData(LeftOver)
Get SourceFile, , ByteData()
Rs(1).AppendChunk ByteData()
ReDim ByteData(BlockSize)
For i = 1 To Numblocks
Get SourceFile, , ByteData()
Rs(1).AppendChunk ByteData()
Next i
Rs.Update 'Commit the new data.
Close SourceFile
End If
End Sub
尝试将图像保存到特定记录时,发生运行时错误:不一致的数据类型,预期的 BLOB 得到编号 Where as: ?sql UPDATE STUDENT_RECORD_DATABASE SET ROLLNO= 132,PICS=688195876 WHERE ROLLNO= 132