Go combat--golang in PDF (Rsc.io/pdf, jung-kurt/gofpdf, Signintech/gopdf)

This is a creation in Article, where the information may have evolved or changed.

Life goes on and on go Go go!!!

Yesterday describes how Excel is manipulated in Golang:
Go combat –golang Excel (Tealeg/xlsx, 360entsecgroup-skylar/excelize)

So let's share with you today how PDFs work in Golang.

PDF Introduction

The Portable Document format (PDF) is a file format used to present documents in a manner independent of application SOFTW is, hardware, and operating systems. [3] Each PDF file encapsulates a complete description of a Fixed-layout flat document, including the text, fonts, graphics , and other information needed to display it.

PDF (abbreviated as "Portable Document Format"), which is used by Adobe Systems for file exchange with application, operating system, and hardware portable, is a file format that is displayed on the document. The PDF file is based on a PostScript language image model that guarantees accurate color and accurate printing on any printer, that is, the PDF faithfully reproduces every character, color, and image of the original.

Rsc.io/pdf

GitHub Address:
Https://github.com/rsc/pdf

star:202

Document Address:
Https://godoc.org/rsc.io/pdf

Get:

get rsc.io/pdf

Read PDF file to get total pages

package main

import (
    "fmt"

    "rsc.io/pdf"
)

func main() {
    file, err := pdf.Open("go.pdf")
    if err != nil {
        panic(err)
    }
    fmt.Println(file.NumPage())
}

Read the contents of a page

package main

import (
    "fmt"

    "rsc.io/pdf"
)

func main() {
    file, err := pdf.Open("test.pdf")
    if err != nil {
        panic(err)
    }
    fmt.Println(file.Page(2).Content())
}

Jung-kurt/gofpdf

Note: The library does not support Chinese!!!

GitHub Address:
Https://github.com/jung-kurt/gofpdf

star:733

Document Address:
Https://godoc.org/github.com/jung-kurt/gofpdf

Get:

go get github.com/jung-kurt/gofpdf

Generate PDF documents

package main

import (
    "fmt"

    "github.com/jung-kurt/gofpdf"
)

func main() {
    pdf := gofpdf.New("P", "mm", "A4", "")
    pdf.AddPage()
    pdf.SetFont("Arial", "B", 26)
    pdf.Cell(40, 10, "Hello PDF World")
    err := pdf.OutputFileAndClose("write_pdf.pdf")
    if err != nil {
        fmt.Println(err)
    }
}

Generate an encrypted PDF

package main

import (
    "fmt"

    "github.com/jung-kurt/gofpdf"
)

func main() {
    pdf := gofpdf.New("P", "mm", "A4", "")
    pdf.SetProtection(gofpdf.CnProtectPrint, "123", "abc")
    pdf.AddPage()
    pdf.SetFont("Arial", "", 12)
    pdf.Write(10, "You Must Enter the Password!!!")
    err := pdf.OutputFileAndClose("write_pdf_with_password.pdf")
    if err != nil {
        fmt.Println(err)
    }
}

Insert a picture in PDF

package main

import (
    "fmt"

    "github.com/jung-kurt/gofpdf"
)

func main() {
    pdf := gofpdf.New("P", "mm", "A4", "")
    pdf.AddPage()
    pdf.SetFont("Arial", "", 11)
    pdf.Image("test.png", 10, 10, 30, 0, false, "", 0, "")
    pdf.Text(50, 20, "test.png")
    pdf.Image("test.gif", 10, 40, 30, 0, false, "", 0, "")
    pdf.Text(50, 50, "test.gif")
    pdf.Image("test.jpg", 10, 130, 30, 0, false, "", 0, "")
    pdf.Text(50, 140, "test.jpg")

    err := pdf.OutputFileAndClose("write_pdf_with_image.pdf")
    if err != nil {
        fmt.Println(err)
    }
}

Add links, HTML in pdf

package main

import (
    "fmt"

    "github.com/jung-kurt/gofpdf"
)

func main() {
    pdf := gofpdf.New("P", "mm", "A4", "")
    pdf.AddPage()
    pdf.SetFont("Helvetica", "", 20)
    _, lineHt := pdf.GetFontSize()
    pdf.Write(lineHt, "To find out what's new in this tutorial, click ")
    pdf.SetFont("", "U", 0)
    link := pdf.AddLink()
    pdf.WriteLinkID(lineHt, "here", link)
    pdf.SetFont("", "", 0)
    // Second page: image link and basic HTML with link
    pdf.AddPage()
    pdf.SetLink(link, 0, -1)
    pdf.Image("test.png", 10, 12, 30, 0, false, "", 0, "http://blog.csdn.net/wangshubo1989?viewmode=contents")
    pdf.SetLeftMargin(45)
    pdf.SetFontSize(14)
    _, lineHt = pdf.GetFontSize()
    htmlStr := `You can now easily print text mixing different styles: <b>bold</b>, ` +
        `<i>italic</i>, <u>underlined</u>, or <b><i><u>all at once</u></i></b>!<br><br>` +
        `<center>You can also center text.</center>` +
        `<right>Or align it to the right.</right>` +
        `You can also insert links on text, such as ` +
        `<a href="http://www.fpdf.org">http://blog.csdn.net/wangshubo1989?viewmode=contents</a>, or on an image: click on the logo.`
    html := pdf.HTMLBasicNew()
    html.Write(lineHt, htmlStr)
    err := pdf.OutputFileAndClose("write_html.pdf")
    if err != nil {
        fmt.Println(err)
    }
}

Signintech/gopdf

Since Jung-kurt/gofpdf does not support Chinese, it introduces a signintech/gopdf that supports Chinese.

GitHub Address:
Https://github.com/signintech/gopdf

star:422

Get:

go get -u github.com/signintech/gopdf

Generate PDF files

To be cool, download a font yourself from the Web.

Package main

Import (
     "log"

     "github.com/signintech/gopdf"
)

Func main() {

     Pdf := gopdf.GoPdf{}
     pdf.Start(gopdf.Config{PageSize: gopdf.Rect{W: 595.28, H: 841.89}}) //595.28, 841.89 = A4
     pdf.AddPage()
     Err := pdf.AddTTFFont("wts11", "TTENuoJ_0.ttf")
     If err != nil {
         log.Print(err.Error())
         Return
     }

     Err = pdf.SetFont("wts11", "", 14)
     If err != nil {
         log.Print(err.Error())
         Return
     }
     pdf.Cell(nil, "I closed my eyes in the fragrant mist of the temple, and suddenly heard the truth in your chanting;")
     pdf.WritePdf("hello.pdf")

}