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
SQL Server中删除重复数据的几个方法
SQL Server 基础概念集
SQL Server导入导出
SQL SERVER实用技巧
sql server 常用函数
如何维护SQL Server的“交易日志”
SQL Server数据备份处理过程探讨
JSP中tomcat的SQL Server2000数据库连接池的配置
SQL Server服务器安装剖析
SQL Server 2005数据加密技术应用研究
SQL Server数据库的备份和恢复措施
SQL Server 2005性能测试实践
Jboss下MS SQL Server配置指导
Oracle和SQL Server 追求完美还是讲求实用
SQL Server服务器安装剖析
SQL Server:Oracle与SQL Server事务处理的比较
SQL Server:利用配置文件实现SQL Server与Oralce访问类的转换
SQL Server:测试SQL Server业务规则链接方法
SQL Server :SQL Server 2008高可用性解决方案优劣分析
SQLServer:数据库恢复

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: 36 ::
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

    '