当前位置: 首页 > 图文教程 > 数据库 > MSSQL > 用VB6读写数据库中的图片

MSSQL
拷贝的SQL Server 7数据库的恢复方法
SQL Server全文检索简介
SQL Server 7.0 一般问题
数据库的查、增、删、改
SQL Server 2000的数据转换服务(下)
SQL Server 2000的数据转换服务(中)
SQL Server 2000的数据转换服务(上)
在SQL2k降序索引上使用中bug
在SQLServer中怎么样恢复数据的存储?
如何将图片存到数据库中?
win98+PWS环境下连接读取远程SQLServer
用SQLServer2000索引视图提高性能(上)
用SQLServer2000索引视图提高性能(下)
如何利用数据库储存图档
袖珍数据库连接查询手册
sql2k增加的Function的sqlbook的帮助
SQL Server静态页面导出技术3
SQL Server静态页面导出技术4
最简便的备份MySql数据库方法
将Access数据库移植到SQL Server 7.0

MSSQL 中的 用VB6读写数据库中的图片


出处:互联网   整理: 软晨网(RuanChen.com)   发布: 2009-10-30   浏览: 65 ::
收藏到网摘: n/a

  很多兄弟在这里问关于VB6读写数据库中的图片的问题,在此有一例,希有所启发。
   1,以人名和相关图片为例说明,数据库为Access,有如下字段:Name char,picture OLE object,FileLength Number。当为ms sql时,将picture改为lob即可。
   2,示例包含control:commom dialog,picture,listbox。
源码如下:
Option Explicit

Private Declare Function GetTempFileName Lib "kernel32" Alias "GetTempFileNameA" (ByVal lpszPath As String, ByVal lpPrefixString As String, ByVal wUnique As Long, ByVal lpTempFileName As String) As Long
Private Declare Function GetTempPath Lib "kernel32" Alias "GetTempPathA" (ByVal nBufferLength As Long, ByVal lpBuffer As String) As Long
Private Const MAX_PATH = 260

Private m_DBConn As ADODB.Connection

Private Const BLOCK_SIZE = 10000
' Return a temporary file name.
Private Function TemporaryFileName() As String
Dim temp_path As String
Dim temp_file As String
Dim length As Long

    ' Get the temporary file path.
    temp_path = Space$(MAX_PATH)
    length = GetTempPath(MAX_PATH, temp_path)
    temp_path = Left$(temp_path, length)

    ' Get the file name.
    temp_file = Space$(MAX_PATH)
    GetTempFileName temp_path, "per", 0, temp_file
    TemporaryFileName = Left$(temp_file, InStr(temp_file, Chr$(0)) - 1)
End Function
Private Sub Form_Load()
Dim db_file As String
Dim rs As ADODB.Recordset

    ' Get the database file name.
    db_file = App.Path
    If Right$(db_file, 1) <> "\" Then db_file = db_file & "\"
    db_file = db_file & "dbpict.mdb"

    ' Open the database connection.
    Set m_DBConn = New ADODB.Connection
    m_DBConn.Open _
        "Provider=Microsoft.Jet.OLEDB.4.0;" & _
        "Data Source=" & db_file & ";" & _
        "Persist Security Info=False"

    ' Get the list of people.
    Set rs = m_DBConn.Execute("SELECT Name FROM People ORDER BY Name", , adCmdText)
    Do While Not rs.EOF
        lstPeople.AddItem rs!Name
        rs.MoveNext
    Loop

    rs.Close
    Set rs = Nothing
End Sub
Private Sub Form_Resize()
    lstPeople.Height = ScaleHeight
End Sub


' Display the clicked person.
Private Sub lstPeople_Click()
Dim rs As ADODB.Recordset
Dim bytes() As Byte
Dim file_name As String
Dim file_num As Integer
Dim file_length As Long
Dim num_blocks As Long
Dim left_over As Long
Dim block_num As Long
Dim hgt As Single

    picPerson.Visible = False
    Screen.MousePointer = vbHourglass
    DoEvents

    ' Get the record.
    Set rs = m_DBConn.Execute("SELECT * FROM People WHERE Name='" & _
        lstPeople.Text & "'", , adCmdText)
    If rs.EOF Then Exit Sub

    ' Get a temporary file name.
    file_name = TemporaryFileName()

    ' Open the file.
    file_num = FreeFile
    Open file_name For Binary As #file_num

    '