include.vb

图书馆管理系统,是数据库的课程设计,报告里面包含了需求分析数据字典概念结构设计逻辑结构设计数据库物理设计数据库实施

Imports System.Data
Imports System.DBNull
Imports System.Data.OleDb

Imports System
Imports System.IO

'引入ADO.NET操作命名空间


Module Include
    Dim fileName As String = "library.mdb"

    Function getpath() '返回数据库完整路径
        Return Path.GetFullPath(fileName) '返回数据库完整路径
    End Function

    Dim sqlstr As String 'SQL语句标记
    Dim objDS As DataSet '数据在内存中的缓存

    Public cmd As OleDbCommandBuilder

    Dim connstring As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & getpath() & ""

    Public conn As OleDbConnection = New OleDbConnection(connstring)
    '定义一个数据连接对象，并初始化

    Public ds As DataSet
    '定义一个数据集对象

    Public myCmd As OleDbCommand
    Public ADOcmd As OleDbDataAdapter

    Public Function GetData(ByVal sqlstr As String) As DataSet
        ds = New DataSet
        ds.Clear()
        '实例化一个数据集对象
        Try
            conn.Open()
            '打开数据库连接
            ADOcmd = New OleDbDataAdapter(sqlstr, conn)
            '将数据库的数据映射到数据适配器
            ADOcmd.Fill(ds)
            '填充数据集的数据
            conn.Close()
            '关闭数据连接，这一点很重要
        Catch
            MsgBox("错误号：" & Err.Number & "错误描述：" & Err.Description)
        End Try
        Return ds
        ds = Nothing
    End Function

    Public Function UpdateData(ByVal sqlstr As String) As Boolean
        Try
            myCmd = New OleDbCommand(sqlstr, conn)
            '要对数据源执行的 SQL 语句或存储过程。
            conn.Open()
            '打开数据库连接
            myCmd.ExecuteNonQuery()
            '执行SQL
            conn.Close()
            '关闭数据库连接
        Catch
            MsgBox("错误号：" & Err.Number & "错误描述：" & Err.Description)
            Return False
        End Try
        Return True
    End Function

    Function filter(ByVal fString) As String  '输入过滤，过滤掉敏感字符 ' " + &
        If fString.length <> 0 Then
            fString = Replace(fString, Chr(34), "") '过滤"
            fString = Replace(fString, Chr(38), "") '过滤&
            fString = Replace(fString, Chr(39), "") '过滤'
            fString = Replace(fString, Chr(43), "") '过滤+
            fString = Replace(fString, Chr(124), "") '过滤|
            Return fString
        End If
    End Function

    Function isnum(ByVal fString) As Boolean
        If fString <> "" Then
            Dim dai As String, dainum As Integer
            For dainum = 1 To fString.Length '检测输入是否数字
                dai = Mid(fString, dainum, 1)
                If Asc(dai) < 48 Or Asc(dai) > 57 Then Return False '比较ASCII码
            Next
            Return True
        End If
    End Function

    Function showadminname(ByVal adminid) As String
        sqlstr = "select * from admininfo where id=" & adminid & ""
        objDS = GetData(sqlstr)
        If objDS.Tables(0).Rows.Count() > 0 Then
            Return objDS.Tables(0).Rows(0)("adminname").ToString
        Else
            Return "不详"
        End If
    End Function

    Function showclassifyname(ByVal classifyid) As String
        sqlstr = "select * from classify where id=" & classifyid & ""
        objDS = GetData(sqlstr)
        If objDS.Tables(0).Rows.Count() > 0 Then
            Return objDS.Tables(0).Rows(0)("name").ToString
        Else
            Return "不详"
        End If
    End Function
End Module