英文:
Print data grid view skips the first row
问题
我已为我想要打印的数据网格视图创建了打印预览。代码运行正常，但存在轻微问题。
问题截图：
在数据网格视图行中，ID 1 不见了，它总是从2开始。我该如何解决这个问题？请帮助。
我的代码：
Private Sub PrintDocument1_PrintPage(sender As System.Object, e As System.Drawing.Printing.PrintPageEventArgs) Handles PrintDocument1.PrintPage
Dim mRow As Integer = 0
Dim newpage As Boolean = True
PrintDocument1.DefaultPageSettings.Landscape = True
With DataGridView1
Dim fmt As StringFormat = New StringFormat(StringFormatFlags.LineLimit)
fmt.LineAlignment = StringAlignment.Center
fmt.Trimming = StringTrimming.EllipsisCharacter
Dim y As Single = e.MarginBounds.Top
Do While mRow < .RowCount
Dim row As DataGridViewRow = .Rows(mRow)
Dim x As Single = e.MarginBounds.Left
Dim h As Single = 0
For Each cell As DataGridViewCell In row.Cells
Dim rc As RectangleF = New RectangleF(x, y, cell.Size.Width, cell.Size.Height)
e.Graphics.DrawRectangle(Pens.Black, rc.Left, rc.Top, rc.Width, rc.Height)
If (newpage) Then
e.Graphics.DrawString(DataGridView1.Columns(cell.ColumnIndex).HeaderText, .Font, Brushes.Black, rc, fmt)
Else
e.Graphics.DrawString(DataGridView1.Rows(cell.RowIndex).Cells(cell.ColumnIndex).FormattedValue.ToString(), .Font, Brushes.Black, rc, fmt)
End If
x += rc.Width
h = Math.Max(h, rc.Height)
Next
newpage = False
y += h
mRow += 1
If y + h > e.MarginBounds.Bottom Then
e.HasMorePages = True
mRow -= 1
newpage = True
Exit Sub
End If
Loop
mRow = 0
End With
End Sub
英文:
I have created a print preview for the data grid view that I want to print. The code works fine but there is slight problem
Problem Screenshot:
In the data grid view row, the ID 1 is missing, it always starts from 2. How can I solve this problem? Please help.
My code:
Private Sub PrintDocument1_PrintPage(sender As System.Object, e As System.Drawing.Printing.PrintPageEventArgs) Handles PrintDocument1.PrintPage
Dim mRow As Integer = 0
Dim newpage As Boolean = True
PrintDocument1.DefaultPageSettings.Landscape = True
With DataGridView1
Dim fmt As StringFormat = New StringFormat(StringFormatFlags.LineLimit)
fmt.LineAlignment = StringAlignment.Center
fmt.Trimming = StringTrimming.EllipsisCharacter
Dim y As Single = e.MarginBounds.Top
Do While mRow < .RowCount
Dim row As DataGridViewRow = .Rows(mRow)
Dim x As Single = e.MarginBounds.Left
Dim h As Single = 0
For Each cell As DataGridViewCell In row.Cells
Dim rc As RectangleF = New RectangleF(x, y, cell.Size.Width, cell.Size.Height)
e.Graphics.DrawRectangle(Pens.Black, rc.Left, rc.Top, rc.Width, rc.Height)
If (newpage) Then
e.Graphics.DrawString(DataGridView1.Columns(cell.ColumnIndex).HeaderText, .Font, Brushes.Black, rc, fmt)
Else
e.Graphics.DrawString(DataGridView1.Rows(cell.RowIndex).Cells(cell.ColumnIndex).FormattedValue.ToString(), .Font, Brushes.Black, rc, fmt)
End If
x += rc.Width
h = Math.Max(h, rc.Height)
Next
newpage = False
y += h
mRow += 1
If y + h > e.MarginBounds.Bottom Then
e.HasMorePages = True
mRow -= 1
newpage = True
Exit Sub
End If
Loop
mRow = 0
End With
End Sub
答案1
得分: 0
If (newpage) 导致绘制标题而不是第一行。
您可以将部分更改为：
If not newpage Then
mRow += 1
End If
newpage = False
y += h
英文:
The If (newpage) causes it to draw the headers instead of the first row.
You could change the section
newpage = False
y += h
mRow += 1
to
If not newpage Then
mRow += 1
End If
newpage = False
y += h
答案2
得分: 0
rows(0) 是第一行数据，不是标题行，而 cell.RowIndex 为 1，所以将 rows(cell.RowIndex) 更改为 rows(cell.RowIndex-1)：
e.Graphics.DrawString(DataGridView1.Rows(cell.RowIndex - 1).Cells(cell.ColumnIndex).FormattedValue.ToString(), .Font, Brushes.Black, rc, fmt)
英文:
rows(0) is the first data row, not header row, while cell.RowIndex is 1, so change rows(cell.RowIndex) as rows(cell.RowIndex-1) :
e.Graphics.DrawString(DataGridView1.Rows(cell.RowIndex - 1).Cells(cell.ColumnIndex).FormattedValue.ToString(), .Font, Brushes.Black, rc, fmt)
答案3
得分: 0
'打印每个部分以避免此类问题。标题部分属于 [`Columns`][1] 集合，所以在处理 `Rows` 和 `Cells` 部分之前，先打印它。
您的代码中还有另一个问题需要修复。`mRow` 是一个 _本地_ 变量，不保留最后打印的行以跳过或新行以继续的信息，当您请求新页面时。它必须是一个 _类_ 字段。
```vb.net
Private mRow As Integer
Private Sub PrintPreviewButton(sender As Object, e As EventArgs) _
Handles Button1.Click
PrintDocument1.DefaultPageSettings.Landscape = True
mRow = 0
Using d = New PrintPreviewDialog With {
.Document = PrintDocument1
}
d.ShowDialog(Me)
End Using
End Sub
Private Sub PrintDocument1_PrintPage(sender As Object, e As PrintPageEventArgs) _
Handles PrintDocument1.PrintPage
Dim g = e.Graphics
Dim x As Integer = e.MarginBounds.X
Dim y As Integer = e.MarginBounds.Y
With DataGridView1
Using sf = New StringFormat(StringFormat.GenericTypographic) With {
.LineAlignment = StringAlignment.Center,
.Trimming = StringTrimming.EllipsisCharacter
}
For Each col As DataGridViewColumn In .Columns
Dim rect = New Rectangle(
x, y,
col.Width, col.DataGridView.ColumnHeadersHeight)
g.DrawRectangle(Pens.Black, rect)
rect.Inflate(-3, 0)
g.DrawString(col.HeaderText, .Font, Brushes.Black, rect, sf)
x += col.Width
Next
y += .ColumnHeadersHeight
For i = mRow To .RowCount - 1
Dim row = .Rows(i)
If row.IsNewRow Then Exit Sub
x = e.MarginBounds.X
For Each cell As DataGridViewCell In row.Cells
Dim rect = New Rectangle(New Point(x, y), cell.Size)
g.DrawRectangle(Pens.Black, rect)
rect.Inflate(-3, 0)
g.DrawString(cell.FormattedValue?.ToString(),
.Font, Brushes.Black, rect, sf)
x += cell.Size.Width
Next cell
y += row.Height
If y + row.Height > e.MarginBounds.Bottom Then
mRow = i + 1
e.HasMorePages = True
Exit For
End If
Next i
End Using
End With
End Sub
<details>
<summary>英文:</summary>
Print each part separately to avoid this kind of problems. The headers part belongs to the [`Columns`][1] collection then print it first before you handle the `Rows` and `Cells` parts.
You have another problem in your code to fix. The `mRow` is a _local_ variable that does not preserve the last printed row to skip or the new row to continue with when you request a new page. It must be a _class_ field.
```vb.net
Private mRow As Integer
Private Sub PrintPreviewButton(sender As Object, e As EventArgs) _
Handles Button1.Click
PrintDocument1.DefaultPageSettings.Landscape = True
mRow = 0
Using d = New PrintPreviewDialog With {
.Document = PrintDocument1
}
d.ShowDialog(Me)
End Using
End Sub
Private Sub PrintDocument1_PrintPage(sender As Object, e As PrintPageEventArgs) _
Handles PrintDocument1.PrintPage
Dim g = e.Graphics
Dim x As Integer = e.MarginBounds.X
Dim y As Integer = e.MarginBounds.Y
With DataGridView1
Using sf = New StringFormat(StringFormat.GenericTypographic) With {
.LineAlignment = StringAlignment.Center,
.Trimming = StringTrimming.EllipsisCharacter
}
For Each col As DataGridViewColumn In .Columns
Dim rect = New Rectangle(
x, y,
col.Width, col.DataGridView.ColumnHeadersHeight)
g.DrawRectangle(Pens.Black, rect)
rect.Inflate(-3, 0)
g.DrawString(col.HeaderText, .Font, Brushes.Black, rect, sf)
x += col.Width
Next
y += .ColumnHeadersHeight
For i = mRow To .RowCount - 1
Dim row = .Rows(i)
If row.IsNewRow Then Exit Sub
x = e.MarginBounds.X
For Each cell As DataGridViewCell In row.Cells
Dim rect = New Rectangle(New Point(x, y), cell.Size)
g.DrawRectangle(Pens.Black, rect)
rect.Inflate(-3, 0)
g.DrawString(cell.FormattedValue?.ToString(),
.Font, Brushes.Black, rect, sf)
x += cell.Size.Width
Next cell
y += row.Height
If y + row.Height > e.MarginBounds.Bottom Then
mRow = i + 1
e.HasMorePages = True
Exit For
End If
Next i
End Using
End With
End Sub
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