Go实战--golang中操作PDF(rsc.io/pdf、jung-kurt/gofpdf、signin

生命不止，继续 go go go !!!

昨天介绍了golang中如何操作excel：
Go实战–golang中操作excel(tealeg/xlsx、360EntSecGroup-Skylar/excelize)

那么今天就跟大家分享一下，golang中如何操作PDF。

PDF简介

The Portable Document Format (PDF) is a file format used to present documents in a manner independent of application software,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（Portable Document Format的简称，意为“便携式文档格式”），是由Adobe Systems用于与应用程序、操作系统、硬件无关的方式进行文件交换所发展出的文件格式。PDF文件以PostScript语言图象模型为基础，无论在哪种打印机上都可保证精确的颜色和准确的打印效果，即PDF会忠实地再现原稿的每一个字符、颜色以及图象。

rsc.io/pdf

github地址：
https://github.com/rsc/pdf

Star: 202

文档地址：
https://godoc.org/rsc.io/pdf

获取：

go get rsc.io/pdf

读取PDF文件，获取总页数

package main

import (
    "fmt"

    "rsc.io/pdf"
)

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

读取某一页的内容

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

注意：该库不支持中文！！！

github地址：
https://github.com/jung-kurt/gofpdf

Star: 733

文档地址：
https://godoc.org/github.com/jung-kurt/gofpdf

获取：

go get github.com/jung-kurt/gofpdf

生成PDF文档

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)
    }
}

生成加密的PDF

package main

import (
    "fmt"

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

func main() {
    pdf := gofpdf.New("P","")
    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)
    }
}

PDF中插入图片

package main

import (
    "fmt"

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

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

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

PDF中增加链接、HTML

package main

import (
    "fmt"

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

func main() {
    pdf := gofpdf.New("P","")
    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, -1)
    pdf.Image("test.png", 12,"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

既然jung-kurt/gofpdf不支持中文，那么就介绍一个支持中文的signintech/gopdf。

github地址：
https://github.com/signintech/gopdf

Star: 422

获取：

go get -u github.com/signintech/gopdf

生成PDF文件

为了炫酷一点，自己从网上下载一个字体。

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,"我闭目在经殿的香雾中， 蓦然听见你颂经中的真言；")
    pdf.WritePdf("hello.pdf")

}