问题
I was wondering what would be the best approach for creating tables in a pdf that have rounded corners using the iTextSharp 5.x+ library.
回答1:
If you have iTextSharp source code, add the following to PdfContentByte class:
/// <summary>
/// Enumuration for defining corners you want rounded.
/// </summary>
[Flags()]
public enum Corners {None = 0,All=15,Top=3,Bottom=12, TopLeft = 1, TopRight=2, BottomLeft=4, BottomRight=8};
/// <summary>
/// Adds a round rectangle to the current path, with rounded conrners as specified by roundCorners.
/// </summary>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="w"></param>
/// <param name="h"></param>
/// <param name="r"></param>
/// <param name="roundCorners"></param>
public void RoundRectangle(float x, float y, float w, float h, float r,Corners roundCorners)
{
if (w < 0)
{
x += w;
w = -w;
}
if (h < 0)
{
y += h;
h = -h;
}
if (r < 0)
r = -r;
float b = 0.4477f;
if((roundCorners & Corners.BottomLeft) == Corners.BottomLeft)
MoveTo(x + r, y);
else
MoveTo(x, y);
if ((roundCorners & Corners.BottomRight) == Corners.BottomRight)
{
LineTo(x + w - r, y);
CurveTo(x + w - r * b, y, x + w, y + r * b, x + w, y + r);
}
else
LineTo(x + w, y);
if ((roundCorners & Corners.TopRight ) == Corners.TopRight)
{
LineTo(x + w, y + h - r);
CurveTo(x + w, y + h - r * b, x + w - r * b, y + h, x + w - r, y + h);
}
else
LineTo(x + w, y + h);
if ((roundCorners & Corners.TopLeft) == Corners.TopLeft)
{
LineTo(x + r, y + h);
CurveTo(x + r * b, y + h, x, y + h - r * b, x, y + h - r);
}
else
LineTo(x , y + h);
if ((roundCorners & Corners.BottomLeft) == Corners.BottomLeft)
{
LineTo(x, y + r);
CurveTo(x, y + r * b, x + r * b, y, x + r, y);
}else
LineTo(x, y);
}
Next step is to implment IPdfPCellEvent interface:
public class myCellEvent : IPdfPCellEvent
{
#region members
PdfContentByte.Corners _roundedCorners;
float _roundness;
#endregion
#region ctor
public myCellEvent()
:this( PdfContentByte.Corners.All,2f)
{
}
public myCellEvent(PdfContentByte.Corners roundedCorners)
: this(roundedCorners, 2f)
{
}
public myCellEvent(PdfContentByte.Corners roundedCorners,float roundness)
{
_roundedCorners = roundedCorners;
_roundness = roundness;
}
#endregion
#region IPdfPCellEvent Members
public void CellLayout(PdfPCell cell, Rectangle position, PdfContentByte[] canvases)
{
PdfContentByte cb = canvases[PdfPTable.LINECANVAS];
cb.RoundRectangle(position.Left, position.Bottom, position.Right - position.Left, position.Top - position.Bottom, this._roundness, this._roundedCorners);
cb.SetColorStroke(new BaseColor(System.Drawing.Color.Black));
cb.SetColorFill(new BaseColor(System.Drawing.Color.Beige));
cb.FillStroke();
cb.Stroke();
}
#endregion
}
Then you round what ever corners you want to produce the rounded table of choice:
PdfPTable table = new PdfPTable(1);
PdfPCell cell = new PdfPCell(new Phrase(10, atext, f2));
cell.Border = 0;
cell.Padding = 5f;
cell.CellEvent = new myCellEvent(PdfContentByte.Corners.Top,2f);
table.AddCell(cell);
If you like the answer ... give it a vote :)
回答2:
There's no way to create an iTextSharp PdfPTable with rounded corners but what you could do is draw a table border with rounded corners using the PdfContentByte.RoundRectangle() method.
Here's a snippet that demonstrates this:
Document doc = new Document();
using (FileStream fs = new FileStream("RoundRectangle Demo.pdf", FileMode.Create)) {
PdfWriter writer = PdfWriter.GetInstance(doc, fs);
doc.Open();
PdfContentByte cb = writer.DirectContent;
// Bottom left coordinates x & y, followed by width, height and radius of corners.
cb.RoundRectangle(100f, 500f, 200f, 200f, 2f);
cb.Stroke();
doc.Close();
}
This snippet is a condensed version of code I found in the article iTextSharp - Drawing shapes and Graphics on www.mikesdotnetting.com. You'll want to take a close look at his other articles if you haven't already.
回答3:
I assume that if you are wanting a table with rounded corners, you're looking for some flashy (or at least pretty) formatting on your table. If that is the case, I would recommend turning off all the borders in your iTextSharp table, and using a graphic image as the background on your page. You can then make the graphic background as intricate and fancy as you want (shading, gradients, rounded corners, etc.) with very little trouble. Then, just line up your table with the background image.
If your data format will change often, you will not want to use this approach.
回答4:
Private Function pdfDIF() As Byte() Dim celevent As New PdfPCellEvent
Dim tableImportes As New PdfPTable(1)
tableImportes.SetTotalWidth({10 * dpixcm})
Dim cellImportes = New PdfPCell(New Phrase("IMPORTE", COURIER9Bold))
cellImportes.BorderWidth = 0
cellImportes.HorizontalAlignment = Element.ALIGN_CENTER
cellImportes.CellEvent = celevent
tableImportes.AddCell(cellImportes)
end function
Public Class PdfPCellEvent Implements IPdfPCellEvent
Public Sub CellLayout(cell As iTextSharp.text.pdf.PdfPCell, position As iTextSharp.text.Rectangle, canvases() As iTextSharp.text.pdf.PdfContentByte) Implements iTextSharp.text.pdf.IPdfPCellEve`enter code here`nt.CellLayout
Dim cb As PdfContentByte = canvases(PdfPTable.LINECANVAS)
cb.RoundRectangle(position.Left,position.Bottom,position.Width,position.Height,10)
cb.SetLineWidth(1)
cb.SetCMYKColorStrokeF(0.0F, 0.0F, 0.0F, 1.0F)
cb.Stroke()
End Sub
End Class
来源：https://stackoverflow.com/questions/2557217/tables-with-rounded-corners