rails 导出 pdf

方案一：基于web页面的打印生成pdf

在linux上先安装wkhtmltopdf这个软件。再在需要调用的地方写命令行。

system("wkhtmltopdf http://www.baidu.com /fullcalendarBranch/public/my_web_site.pdf")


方案二：生成pdf工具

gem 'prawn'
gem 'prawn-table' 

class OrderPdf < Prawn::Document

  extend ActiveSupport::Autoload
  autoload :PrawnTable

	def initialize(order)
		super()
    font_families["msyh"] = {
      :normal => { :file => "#{Rails.root}/public/pdf/gkai00mp.ttf" },
      :bold => { :file => "#{Rails.root}/public/pdf/gkai00mp.ttf" }
    }
		@order = order
#		font "Times-Roman", :size => 13 do
    font "msyh", :size => 13 do
			logo
			company
			orders
			order_item
		end
	end

	def logo
    bounding_box [0, bounds.top], :width  => bounds.width do
      image "#{Rails.root}/app/assets/images/coa_logo1.png", :width => 190, :height =>90
    end
  end

  def company
		bounding_box [250, bounds.top - 30], :width  => bounds.width do
      text "COMMERCIAL INVOICE", :size => 24, :styles => [:bold, :italic]
      text "#{@order.contact.company.name}"
      move_down 8
      text "Date: #{@order.created_at.format_date(:date)}"
  	end
  end

  def orders
  	bounding_box [0, bounds.top - 120], :width  => bounds.width do
      text "To"
      move_down 8
      text "#{@order.address.contact_person}"
      move_down 8
      text "Phone: #{@order.address.tel}"
      move_down 8
      text "Email: #{@order.address.email}"
      move_down 8
      text "Address: #{@order.address.address}"
    end
    bounding_box [250, bounds.top - 120], :width  => bounds.width do
      text "Invoice: #{@order&.invoice}"
      move_down 8
      text "Order ID: #{@order.uuid}"
      move_down 8
      text "Your PO#: #{@order.po}"
    end
  end

  def order_item
  	bounding_box [0, bounds.top - 290], :width  => bounds.width do
     stroke_horizontal_rule
     items = Array.new() { Array.new() }
     items[0] = ["Catalog No.", "Product", "CAS No.", "Payment Due", "Subtotal"]
     @order.order_items.each_with_index do |item, index|
     		items[index + 1] = [item.chemical.catalog_no, item.chemical.name, item.chemical.cas, item&.overdue_date, "$" + (format "%0.2f", item.amount).to_s ]
     end
     th_style = {
        align: :center,
        valign: :center,
        size: 14,
        font_style: :bold,
        height: 30,
        background_color: 'eeeeee'
     }
     td_style = {
        align: :center,
        valign: :center,
        size: 12
     }
     options = {
        position: :center,
        width: bounds.width
     }

     table(items, options) do
        row(0).style th_style
        row(1..-1).style td_style
     end
     move_down 8
     text "* According to and weight of the above products, a total of $#{@order.handling_fee} package fee will be charged", :size => 10
     move_down 20
     text "Shipping: $#{@order.shipping_fee}", :size => 16, :styles => [:bold, :italic], :align => :right
     move_down 4
     text "Total: $#{@order.amount}", :size => 16, :styles => [:bold, :italic], :align => :right
     move_down 10
     text "Payment Terms: #{Order.enum_i18n(:payment_method, @order.payment_method)}", :size => 16, :styles => [:bold, :italic], :align => :left
     move_down 10
     text "Overdue payment may defer new quotation and order by iChemical.", :size => 12, :styles => [:bold, :italic], :align => :left
    end
  end

end

    pdf = OrderPdf.new(@order)
    send_data pdf.render, filename: 'iChemical Invoice-' << @order.uuid << '.pdf', type: "application/pdf", disposition: "attachment"