[VB.NET] - 打印DataGridView类

Imports System.Drawing.Printing

Public Class PrintDataGridView
    Private WithEvents PrintDocument1 As New Printing.PrintDocument
    Private WithEvents PageSetupDialog1 As New System.Windows.Forms.PageSetupDialog
    Private WithEvents FontDialog1 As New System.Windows.Forms.FontDialog
    Private WithEvents PrintPreviewDialog1 As New System.Windows.Forms.PrintPreviewDialog
    Private DGV As DataGridView
    Private strTitle As String
    Private tsiDisplayStyle As ToolStripItemDisplayStyle = ToolStripItemDisplayStyle.Image
    Private tirTextImageRelation As TextImageRelation = Windows.Forms.TextImageRelation.ImageAboveText
    Private wInc As Single = 5 'wInc 为单元格宽增量
    Private hInc As Single = 5 'hInc 为单元格竖增量
    Private MainStartHeigth As Single 'MainStartHeigth 为主体表格起始的高度
    Shared pNo As Integer = 1 'pNo 为页码
    Private StartHeigth As Single
    Private StartPos As Single
    Shared hi As Integer = 0
    Public PrintFont As Font = New Font("Arial", 16)
    Private ColumnsWidth() As Single '数组 ColumnsWidth 为计算后的列宽
    Private orgColumnsWidth() As Single '数组 orgColumnsWidth 为原始的最大列宽
    Private RowHeigth As Single 'RowHeigth 为计算后的行高

    Sub New()
        AddHandler PrintDocument1.PrintPage, AddressOf Me.pd_PrintMain
    End Sub

    '按钮显示方式
    '遍历整个表格,得到每列的最大宽度
    Private Sub GetLargestWidthOfColumn(ByVal g As System.Drawing.Graphics)
        ReDim ColumnsWidth(DGV.Columns.Count - 1) '定义列宽数组的长度
        ReDim orgColumnsWidth(DGV.Columns.Count - 1)
        For i As Integer = 0 To DGV.Columns.Count - 1
            If DGV.Columns(i).Visible = False Then Continue For '如果列为隐藏,不打印
            ColumnsWidth(i) = DGV.Columns(i).Width
        Next

        Dim iC, iR As Integer
        For iC = 0 To DGV.Columns.Count - 1
            If DGV.Columns(iC).Visible = False Then Continue For '如果列为隐藏,不打印
            Dim dc As DataGridViewColumn = DGV.Columns(iC)
            '计算列头文字需要的宽
            Dim sizeFHeader As Drawing.SizeF
            sizeFHeader = g.MeasureString(dc.HeaderText, PrintFont)
            If sizeFHeader.Width > ColumnsWidth(iC) Then
                orgColumnsWidth(iC) = sizeFHeader.Width
            Else
                If orgColumnsWidth(iC) > ColumnsWidth(iC) * 3 Then
                    orgColumnsWidth(iC) = ColumnsWidth(iC) * 3
                Else
                    orgColumnsWidth(iC) = ColumnsWidth(iC)
                End If
            End If
            RowHeigth = sizeFHeader.Height

            dc.Dispose()
            '计算值的宽
            For iR = 0 To DGV.Rows.Count - 1
                Dim dr As DataGridViewRow = DGV.Rows(iR)
                If dr.Cells(iC).Value IsNot Nothing AndAlso Not IsDBNull(dr.Cells(iC).Value) Then
                    sizeFHeader = g.MeasureString(dr.Cells(iC).Value.ToString, PrintFont)
                    If orgColumnsWidth(iC) < sizeFHeader.Width Then
                        orgColumnsWidth(iC) = sizeFHeader.Width
                    End If

                End If
                dr.Dispose()
            Next
        Next
    End Sub

    '根据纸张宽度,计算出合适的列宽,返回缩小的比例
    Private Function GetFitWidthOfColumn(ByVal pWidth As Single) As Integer
        '每列按原始宽度的1%递减,直到适合纸张宽度(pWidth)
        Dim l, i, k As Integer
        l = orgColumnsWidth.Length
        For k = 100 To 1 Step -1
            Dim WidthSum As Single = 0
            '按比例求宽度
            For i = 0 To l - 1
                ColumnsWidth(i) = orgColumnsWidth(i) * k / 100
                WidthSum += orgColumnsWidth(i) * k / 100 + wInc
            Next
            If Not WidthSum > pWidth Then
                Exit For
            End If
        Next
        Return (k)
    End Function

    '根据合适的列宽和列宽缩小的比例,计算出合适的行高
    Private Sub GetFitHeightOfRow(ByVal pScale As Integer)
        RowHeigth = RowHeigth * Fix((100 / pScale) + 1) + hInc
    End Sub

    '打印主体
    Private Sub pd_PrintMain(ByVal sender As Object, ByVal e As System.Drawing.Printing.PrintPageEventArgs)
        Dim g As Graphics = e.Graphics
        '如果是第一页,计算长宽
        If pNo = 1 Then
            GetLargestWidthOfColumn(g)
            GetFitHeightOfRow(GetFitWidthOfColumn(e.MarginBounds.Width))
        End If
        '添加DataGridView主体
        '计算标题的高度,预留空间
        Dim sizeFTitle As Drawing.SizeF
        sizeFTitle = e.Graphics.MeasureString(Title, New Font("宋体", 30, FontStyle.Bold))
        MainStartHeigth = sizeFTitle.Height + e.MarginBounds.Top
        StartHeigth = MainStartHeigth
        '-------------------再来开始------------------------
        '添加列头,按已经求出的最长宽度
        '起始位置为纸张可打印边框的左边
        StartPos = e.MarginBounds.Left
        Dim i As Integer
        For i = 0 To DGV.Columns.Count - 1
            '如果列为隐藏,不打印
            If DGV.Columns(i).Visible = False Then
                Continue For
            End If
            Dim dc As DataGridViewColumn
            dc = DGV.Columns(i)
            Dim sizeFHeader As New Drawing.SizeF
            sizeFHeader = e.Graphics.MeasureString(dc.HeaderText, PrintFont, ColumnsWidth(i))             '写表头
            g.DrawString(dc.HeaderText, PrintFont, Drawing.Brushes.Black, New RectangleF(StartPos + wInc, StartHeigth + hInc, ColumnsWidth(i) - wInc, RowHeigth - hInc))             '添加外边框
            g.DrawLine(Pens.Black, StartPos, StartHeigth, StartPos + ColumnsWidth(i), StartHeigth) '上
            g.DrawLine(Pens.Black, StartPos, StartHeigth, StartPos, StartHeigth + RowHeigth) '左
            StartPos += ColumnsWidth(i)
        Next         '添加主体       
        StartHeigth += RowHeigth
        While hi < DGV.Rows.Count And StartHeigth < e.MarginBounds.Height
            StartPos = e.MarginBounds.Left
            Dim obj As New Object
            Dim wi As Integer = 0
            For wi = 0 To DGV.Columns.Count - 1
                If DGV.Columns(wi).Visible = False Then Continue For '如果列为隐藏,不打印
                Dim dcWidth As Single
                dcWidth = ColumnsWidth(wi)

                g.DrawLine(Pens.Black, StartPos, StartHeigth, StartPos + dcWidth, StartHeigth) '上
                g.DrawLine(Pens.Black, StartPos, StartHeigth, StartPos, StartHeigth + RowHeigth) '左
                StartPos += dcWidth
                Try
                    If Not IsDBNull(DGV.Rows(hi).Cells(wi).Value) Then
                        g.DrawString(DGV.Rows(hi).Cells(wi).Value.ToString(), PrintFont, Drawing.Brushes.Black, New RectangleF(StartPos - dcWidth + 2, StartHeigth + 3, dcWidth + 2, RowHeigth))
                    End If
                Catch ex As Exception
                    MessageBox.Show(ex.Message, "Error!", MessageBoxButtons.OK, MessageBoxIcon.Error)
                End Try
            Next
            StartHeigth += RowHeigth
            hi += 1
        End While
        '如果是第一页,添加表头
        '根据绘制表格的宽度添加标题()
        If pNo = 1 Then
            If StartPos - e.MarginBounds.Left < sizeFTitle.Width Then
                '如果标题的宽度大于表格的宽度,则缩小标题字号
                For i = 30 To 1 Step -1
                    sizeFTitle = e.Graphics.MeasureString(Title, New Font("宋体", i, FontStyle.Bold))
                    If sizeFTitle.Width < StartPos - e.MarginBounds.Left Then
                        g.DrawString(Title, New Font("宋体", i, FontStyle.Bold), Brushes.Black, (StartPos - e.MarginBounds.Left - sizeFTitle.Width) / 2 + e.MarginBounds.Left, (MainStartHeigth - sizeFTitle.Height) / 2)
                        Exit For
                    End If
                Next
            Else
                g.DrawString(Title, New Font("宋体", 30, FontStyle.Bold), Brushes.Black, (StartPos - e.MarginBounds.Left - sizeFTitle.Width) / 2 + e.MarginBounds.Left, (MainStartHeigth - sizeFTitle.Height) / 2)
            End If
        End If

        g.DrawLine(Pens.Black, e.MarginBounds.Left, StartHeigth, StartPos, StartHeigth) '封底
        g.DrawLine(Pens.Black, StartPos, MainStartHeigth, StartPos, StartHeigth) '封右边
        If StartHeigth + RowHeigth > e.MarginBounds.Height And hi < DGV.Rows.Count Then
            e.HasMorePages = True
            pNo += 1 '页码加1
            StartPos = e.MarginBounds.Left
            StartHeigth = e.MarginBounds.Top
        Else
            e.HasMorePages = False
        End If         '结尾标志
        'If hi.Equals(dgv.Rows.Count) Then 'And e.HasMorePages.Equals(False) Then
        If hi >= DGV.Rows.Count Then   'And e.HasMorePages.Equals(False) Then
            hi = 0
            pNo = 1
            Exit Sub
        End If
    End Sub

    '数据源,输入DataGridView
    Public Property MyDataGridView() As DataGridView
        Set(ByVal value As DataGridView)
            DGV = value
        End Set
        Get
            Return DGV
        End Get
    End Property

    '报表标题
    Public Property Title() As String
        Set(ByVal value As String)
            strTitle = value
        End Set
        Get
            Return strTitle
        End Get
    End Property

    '页面设置
    Public Sub PageSetup()
        Me.PageSetupDialog1.Document = Me.PrintDocument1
        Me.PageSetupDialog1.ShowDialog()
        Me.PrintDocument1.DefaultPageSettings = Me.PageSetupDialog1.PageSettings
    End Sub

    '打印预览
    Public Sub PrintPreview()
        Me.PrintPreviewDialog1.Document = Me.PrintDocument1
        Me.PrintPreviewDialog1.ShowDialog()
    End Sub

    '设置字体
    Public Sub PrintPreviewFont()
        Me.FontDialog1.ShowDialog()
        PrintFont = Me.FontDialog1.Font
    End Sub

    '打印
    Public Sub Print()
        Me.PrintDocument1.Print()
    End Sub
End Class