How to draw watermark text whose outline color is red and inner color is gray using iTextSharp

问题

How to draw watermark text whose outline color is red and inner color is gray using iTextSharp

回答1:

If you are using a watermark I'm assuming that you are talking about a PdfStamper. If so, once you've got a raw PdfContentByte using either GetOverContent() or GetUnderContent() there's just a couple of properties that you need to set.

• PdfContentByte.SetLineWidth(single) - set the stroke thickness
• PdfContentByte.SetColorFill(BaseColor.GRAY) - set the fill color. You can also use any of the other color methods such as SetRGBColorFill() or SetCMYKColorFill()
• PdfContentByte.SetColorStroke(BaseColor.RED) - set the stroke color
• PdfContentByte.SetTextRenderingMode(PdfContentByte.TEXT_RENDER_MODE_FILL_STROKE) - flag that you want text to be draw with both a fill and a stroke

Below is a full working WinForms app targetting iTextSharp 5.1.1.0 that puts it all together. You should be able to move this to ASP.Net fairly easily as well as convert it to C# if needed.

Option Explicit On
Option Strict On

Imports iTextSharp.text
Imports iTextSharp.text.pdf
Imports System.IO

Public Class Form1

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        ''//Our sample files
        Dim InputFile = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "Test.pdf")
        Dim OutputFile = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "Test_W_Watermark.pdf")

        ''//Create our input file to watermark later, nothing special here
        Using FS As New FileStream(InputFile, FileMode.Create, FileAccess.Write, FileShare.Read)
            Using Doc As New Document(PageSize.LETTER)
                Using W = PdfWriter.GetInstance(Doc, FS)
                    Doc.Open()

                    Doc.Add(New Paragraph("This is a test"))

                    Doc.Close()
                End Using
            End Using
        End Using


        ''//Watermark the file that we create above

        ''//Bind a reader to our input file
        Dim R As New PdfReader(InputFile)
        ''//Create our output file stream
        Using FS As New FileStream(OutputFile, FileMode.Create, FileAccess.Write, FileShare.Read)
            ''//Bind a stamper to our output file stream
            Using stamper As New PdfStamper(R, FS)
                ''//Grab the raw content byte to draw with
                Dim cb = stamper.GetOverContent(1)

                ''//Flag that we are starting text commands
                cb.BeginText()

                ''//Set the stroke width
                cb.SetLineWidth(2)

                ''//Set the fill (inner) color for the font
                cb.SetColorFill(BaseColor.GRAY)

                ''//Set the stroke (outer) color for the font
                cb.SetColorStroke(BaseColor.RED)

                ''//Flag that when drawing text the system should use both a fill and a stroke
                cb.SetTextRenderingMode(PdfContentByte.TEXT_RENDER_MODE_FILL_STROKE)

                ''//Set a font to draw with
                cb.SetFontAndSize(BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.EMBEDDED), 50)

                ''//Tell the system to start drawing at the center of the first page
                cb.SetTextMatrix(R.GetPageSize(1).Width / 2, R.GetPageSize(1).Height / 2)

                ''//Draw the actual text
                cb.ShowText("Hello")

                ''//Flag that we are done drawing text
                cb.EndText()
            End Using
        End Using
        Me.Close()
    End Sub
End Class

来源：https://stackoverflow.com/questions/7832671/how-to-draw-watermark-text-whose-outline-color-is-red-and-inner-color-is-gray-us