實習日常

vb.net小白的開發日常

研究了一整天的vb.net分頁功能，發現這個需求不用做。。。（是該開心呢？還是開心呢？）
研究了一整天也算是研究出來了
由於不熟悉vb.net和DataGridView控件的使用，所以進行了較長時間的百度型研究；
經過一段時間的分析，我決定通過建立一個PageDataGridViewPage（命名就這水平了…）類，通過實例化該類實現分頁功能（一堆廢話湊字數…）
上代碼：

Imports System.Collections.Generic
Imports DentalLibrary.ShowToothPosition

Public Class PageDataGridViewPage
    '<---test---->
    Private _RowsPerPage As Integer '每頁記錄數
    Private _TotalPage As Integer '總頁數
    Private _CurrentPage As Integer '當前頁數
    Private _tempDetail As New List(Of DeptProcessDetail) '要分頁的List
    'Private _dv As DataView '需要分頁顯示的DataView
    '<----test--->
    '<---test---->
    '獲取與設置每頁記錄數
    Public Property RowsPerPage() As Integer
        Get
            Return _RowsPerPage
        End Get
        Set(ByVal value As Integer)
            _RowsPerPage = value
        End Set
    End Property
    '獲取總頁數
    Public Property TotalPage() As Integer
        Get
            Return _TotalPage
        End Get
        Set(value As Integer)
            _TotalPage = value
        End Set
    End Property
    '獲取與設置當前頁數
    Public Property CurrentPage() As Integer
        Get
            Return _CurrentPage
        End Get
        Set(ByVal value As Integer)
            _CurrentPage = value
        End Set
    End Property
    '設置需要分頁的SetDataGridView
    Public Property SetTempDetail() As List(Of DeptProcessDetail)
        Get
            Return _tempDetail
        End Get
        Set(ByVal value As List(Of DeptProcessDetail))
            _tempDetail = value
        End Set
    End Property
    '設置分頁顯示的DataView
    'Public WriteOnly Property SetDataView() As DataView
    '    Set(ByVal value As DataView)
    '        _dv = value
    '    End Set
    'End Property

    Public Sub New()

        ' 此調用是設計器所必需的。
        'InitializeComponent()
        ' 在 InitializeComponent() 調用之後添加任何初始化。

    End Sub
    '重載New函數，在構造時對成員賦值
    Public Sub New(ByVal TempDetailLst As List(Of DeptProcessDetail), ByVal RowsPerPage As Integer)
        _tempDetail = TempDetailLst
        _RowsPerPage = RowsPerPage
    End Sub
    '分頁
    Public Sub Paging()
        '判斷DataView中的記錄數是否足夠形成多頁，
        '若不能，則只有一頁
        If _tempDetail.Count <= _RowsPerPage Then
            _TotalPage = 1
            GoLastPage()
            Exit Sub
        End If
        '若能分多頁
        If _tempDetail.Count Mod _RowsPerPage = 0 Then
            _TotalPage = Int(_tempDetail.Count / _RowsPerPage)
        Else
            _TotalPage = Int(_tempDetail.Count / _RowsPerPage) + 1
        End If
        GoFirstPage()
    End Sub
    '到第一頁
    Public Sub GoFirstPage()
        '若只有一頁
        If _TotalPage = 1 Then
            GoLastPage()
            Exit Sub
        End If
        '若有多頁
        _CurrentPage = 0
        GoNoPage(_CurrentPage)
    End Sub
    Public Sub GoNextPage()
        _CurrentPage += 1
        If _CurrentPage > _TotalPage - 1 Then
            _CurrentPage = _TotalPage - 1
            Exit Sub
        End If
        '若已達最後一頁，則顯示最後一頁
        If _CurrentPage = _TotalPage - 1 Then
            GoLastPage()
            Exit Sub
        End If
        '若未到最後一頁，就到指定下一頁
        GoNoPage(_CurrentPage)
    End Sub

    Public Sub GoPrevPage()
        _CurrentPage -= 1
        If _CurrentPage < 0 Then
            _CurrentPage = 0
            Exit Sub
        End If
        GoNoPage(_CurrentPage)
    End Sub
    Public Sub GoLastPage()
        Dim LastTempDetail As New List(Of DeptProcessDetail)
        LastTempDetail = _tempDetail.GetRange((TotalPage - 1) * _RowsPerPage, _tempDetail.Count)
        _tempDetail = LastTempDetail
    End Sub
    Public Sub GoNoPage(ByVal PageNo As Integer)
        _CurrentPage = PageNo
        If _CurrentPage < 0 Then
            MsgBox("頁號不能小於1")
            Exit Sub
        End If
        '防止頁號溢出
        If _CurrentPage >= _TotalPage Then
            MsgBox("頁號超出上限")
            Exit Sub
        End If
        '頁號爲最後一頁
        If _CurrentPage = _TotalPage - 1 Then
            GoLastPage()
            Exit Sub
        End If
        '不是最後一頁
        Dim NotLastTempDetail As New List(Of DeptProcessDetail)
        Dim startLocation As Integer = PageNo * _RowsPerPage
        Dim endLocation As Integer = (PageNo + 1) * _RowsPerPage
        If endLocation < RowsPerPage Then
            NotLastTempDetail = _tempDetail.GetRange(startLocation, endLocation)
        Else
            NotLastTempDetail = _tempDetail.GetRange(startLocation, RowsPerPage)
        End If
        _tempDetail = NotLastTempDetail
    End Sub
End Class