gys.vb

用VB开发了一个超市管理系统

Public Class gys
    Shared Function loadgys(ByVal Field As String, ByVal Value As String, ByVal DBOperator As String) As DataTable
        Dim sqlstring As String
        Dim column As String = ""
        column = "gongyingno as 供应商编号,gongyingname as 供应商名称,gongyingaddress as 供应商地址,lianxiren as 联系人,tel as 电话号码"
        If Field = "" Then
            sqlstring = "select " & column & " from gongyingshang order by gongyingno"
        ElseIf DBOperator = "" Then
            sqlstring = "select " & column & " from gongyingshang where " & Field & "=  '" & Value & "' order by gongyingno"
        ElseIf DBOperator = "like" Then
            sqlstring = "select " & column & " from gongyingshang where " & Field & " " & DBOperator & "'" & "%" & Value & "%" & "'order by gongyingno"
        Else
            sqlstring = "select " & column & " from gongyingshang where " & Field & " " & DBOperator & Val(Value) & "order by gongyingno"
        End If
        Return DBOperation.DBOperate(sqlstring)
    End Function
    Shared Sub delgys(ByVal gongyingno As String)
        Dim sqlstring As String
        sqlstring = "delete from gongyingshang where gongyingno='" & gongyingno & "'"
        DBOperation.DBOperate(sqlstring)
    End Sub
    Private _gongyingno As String
    Private _gongyingname As String
    Private _gongyingaddress As String
    Private _lianxiren As String
    Private _tel As String
    Sub New(ByVal gongyingno As String, ByVal gongyingname As String, ByVal gongyingaddress As String, ByVal lianxiren As String, ByVal tel As String)
        _gongyingno = gongyingno
        _gongyingname = gongyingname
        _gongyingaddress = gongyingaddress
        _lianxiren = lianxiren
        _tel = tel
    End Sub
    Function addgys()
        Dim sqlstring As String
        sqlstring = "select * from gongyingshang where gongyingno = '" & _gongyingno & "'"
        Dim usertable As DataTable = DBOperation.DBOperate(sqlstring)
        If usertable.Rows.Count >= 1 Then
            MsgBox("该供应商编号已经存在，请重试", MsgBoxStyle.Exclamation, "信息框")
            Return False
        Else
            sqlstring = "insert into gongyingshang values('" & _gongyingno & "','"
            sqlstring += _gongyingname & "','" & _gongyingaddress & "','"
            sqlstring += _lianxiren & "','" & _tel & "')"
            DBOperation.DBOperate(sqlstring)
            Return True
        End If
    End Function
    Sub updategys()
        Dim sqlstring As String
        sqlstring = "update gongyingshang set gongyingname = '" & _gongyingname & "',gongyingaddress = '" & _gongyingaddress & "',lianxiren = '" & _lianxiren & "',tel = '" & _tel & "' where gongyingno = '" & _gongyingno & "'"
        DBOperation.DBOperate(sqlstring)
    End Sub
End Class