include.vb

来自「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」· VB 代码 · 共 113 行

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