Question

我需要使用Python / Django创建Code128条形码，这些条形码必须嵌入HTML文档中。

我不想在磁盘上制作任何临时（或缓存）文件。这就是我想将它们嵌入数据URI方案的原因。

结果必须是这样的：

<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUA
AAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO
9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Red dot">

你能给我推荐一个简单的方法吗？

现在我使用ReportLab创建这样的条形码并将它们嵌入到PDF文件中，但我不知道如何将它们导出为数据URI方案。如果这是推荐的方法。

Answer 1

这是我自己的解决方案：

from base64 import b64encode
from reportlab.lib import units
from reportlab.graphics import renderPM
from reportlab.graphics.barcode import createBarcodeDrawing
from reportlab.graphics.shapes import Drawing

def get_barcode(value, width, barWidth = 0.05 * units.inch, fontSize = 30, humanReadable = True):

    barcode = createBarcodeDrawing('Code128', value = value, barWidth = barWidth, fontSize = fontSize, humanReadable = humanReadable)

    drawing_width = width
    barcode_scale = drawing_width / barcode.width
    drawing_height = barcode.height * barcode_scale

    drawing = Drawing(drawing_width, drawing_height)
    drawing.scale(barcode_scale, barcode_scale)
    drawing.add(barcode, name='barcode')

    return drawing

def get_image():

    barcode = get_barcode(value = '01234567890', width = 600)
    data = b64encode(renderPM.drawToString(barcode, fmt = 'PNG'))
    print '<img src="data:image/png;base64,{0}">'.format(data)

此外，您还可以将条形码旋转90°：

def get_barcode_rotated(value, width, barWidth = 0.05 * units.inch, fontSize = 30, humanReadable = True):

    barcode = createBarcodeDrawing('Code128', value = value, barWidth = barWidth, fontSize = fontSize, humanReadable = humanReadable)

    drawing_width = width
    barcode_scale = drawing_width / barcode.width
    drawing_height = barcode.height * barcode_scale

    drawing = Drawing(drawing_width, drawing_height)
    drawing.scale(barcode_scale, barcode_scale)
    drawing.add(barcode, name='barcode')

    drawing_rotated = Drawing(drawing_height, drawing_width)
    drawing_rotated.rotate(90)
    drawing_rotated.translate(0, -drawing_height)
    drawing_rotated.add(drawing, name='drawing')

    return drawing_rotated

以下是一个示例结果：

http://pastehtml.com/view/ci7qei4k1.html

Answer 2

这应该可以解决问题。我使用Code128 python模块生成条形码。

<强>码

from Code128 import Code128
from base64 import b64encode

val = "9782212110708"
Code128().getImage(val, path="./")
data = b64encode(open(val + '.png').read())
print '<img src="data:image/png;base64,{0}">'.format(data)

<强>输出

<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAIMAAAAyAQAAAABXcFUb
AAAAjklEQVR4nGP8r2v6J/ihYotFKrs5qx9H2TwmBnQwKjIqMnRFGP+jCTzErkvS6IR80Yu5iScU
GBgYGFgYGP4b3j6t9Xn+ZG4jA6gIAxtDos26ROHFcF2M+32/XPjLwPCX8QLMnAOfXyz4xcDA8B+m
63/djHUCHxkYfkEt+///v8zHJg6GBpbi4/L///9/AADHAS8/nZ4QEQAAAABJRU5ErkJggg==">

<强>更新

在评论中有一个很好的建议来修改Code128模块，这样它就不必将图像保存到文件系统中。您可以更改Code128，使其返回图像对象，而不是将其保存到文件中。您只需要更改一行代码即可实现此目的。从以下地址更改第162行：

im.save(path+value+"."+lower(extension), upper(extension))

为：

return im

Answer 3

您是否尝试使用自己的图像数据表示的每个符号动态组装条形码？这是一个例子：

＆LT; IMG ALT = “105，{出发赛}” 标题= “105，{出发赛}” SRC = “数据：图像/ PNG; BASE64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD /// + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / ACxgALsAjajKmzkAAAAASUVORK5CYII =” 宽度= “30”高度= “60” ＆GT;＆LT; IMG alt =“00，A：{space}，B：{space}”title =“00，A：{space}，B：{space}”src =“data：image / png; base64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD // / + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / ACZgAK8Ah / KrWu0AAAAASUVORK5CYII =“width =”30“height =”60“＆gt;＆lt; img alt =“98，A：{Escape B}，B：{Escape A}”title =“98，A：{Escape B}，B：{Escape A}”src =“data：image / png; base64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD /// + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / AAugALkArBSbglwAAAAASUVORK5CYII =“width =”30“height =”60“＆gt;＆lt; img alt =“21，A：{5}，B：{5}”title =“21，A：{5}，B：{5}”src =“data：image / png; base64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD // / + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / ACNgAKkAhD / i5lYAAAAASUVORK5CYII =“width =”30“height =”60“＆gt;＆lt; img alt =“14，A：{。}，B：{。}”title =“14，A：{。}，B：{。}”src =“data：image / png; base64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD // / + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / AGYgAO8Ah9WahQgAAAAASUVORK5CYII =“width =”30“height =”60“＆gt;＆lt; img alt =“00，A：{space}，B：{space}”title =“00，A：{space}，B：{space}”src =“data：image / png; base64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD // / + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / ACZgAK8Ah / KrWu0AAAAASUVORK5CYII =“width =”30“height =”60“＆gt;＆lt; img alt =“14，A：{。}，B：{。}”title =“14，A：{。}，B：{。}”src =“data：image / png; base64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD // / + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / AGYgAO8Ah9WahQgAAAAASUVORK5CYII =“width =”30“height =”60“＆gt;＆lt; img ALT = “64，A：{NUL}，B：{}" title=" 64,A:{NUL},B:{}” SRC = “数据：图像/ PNG; BASE64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD /// + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / AF5gAR8Av0A69KoAAAAASUVORK5CYII =” 宽度=“30 “height =”60“＆gt;＆lt; img alt =“95，A：{US}，B：{DEL}”title =“95，A：{US}，B：{DEL}”src =“data：image / png; base64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD // / + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / AELgAWcBIz + IUR4AAAAASUVORK5CYII =“width =”30“height =”60“＆gt;＆lt; img alt =“07，A：{'}，B：{'}”title =“07，A：{'}，B：{'}”src =“data：image / png; base64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD // / + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / AGdgATEAyJ / 9LboAAAAASUVORK5CYII =“width =”30“height =”60“＆gt;＆lt; img alt =“74，A：{LF}，B：{j}”title =“74，A：{LF}，B：{j}”src =“data：image / png; base64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD // / + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / AHmgAZUBGuCD0Y8AAAAASUVORK5CYII =“width =”30“height =”60“＆gt;＆lt; img alt =“101，A：{FNC 4}，B：{Switch A}，C：{Switch A}”title =“101，A：{FNC 4}，B：{Switch A}，C：{Switch A }” SRC = “数据：图像/ PNG; BASE64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD /// + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / ABQgAEsANWhuDt4AAAAASUVORK5CYII =” 宽度= “30” HEIGHT = “60” ＆GT;＆LT; IMG alt =“25，A：{9}，B：{9}”title =“25，A：{9}，B：{9}”src =“data：image / png; base64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD // / + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / ABpgAJcAex9glyQAAAAASUVORK5CYII =“width =”30“height =”60“＆gt;＆lt; img alt =“12，A：{，}，B：{，}”title =“12，A：{，}，B：{，}”src =“data：image / png; base64，iVBORw0KGgoAAAANSUhEUgAAAAsAAAABAQMAAAAy + cYDAAAABlBMVEUAAAD // / + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / AExgAPsArevKOWsAAAAASUVORK5CYII =“width =”30“height =”60“＆gt;＆lt; img ALT = “106，{停止}” 标题= “106，{停止}” SRC = “数据：图像/ PNG; BASE64，iVBORw0KGgoAAAANSUhEUgAAAA0AAAABAQMAAAA / 57ZEAAAABlBMVEUAAAD /// + l2Z / dAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAADklEQVQIHQEDAPz / ADigARMA2dpJzT8AAAAASUVORK5CYII =” 宽度= “30” 高度= “60” ＆GT;
009821140014649507749

这代表与您的示例相同的条形码，但不需要中间图形，占用大约三分之一的空间。用于构成图像的数据可以从数组访问，并用于使用Javascript或其他客户端或服务器端应用程序填充目标HTML。

您可以在http://notionovus.com/blog/code-128-barcode/

找到完整的Code 128符号列表

我不确定轮换。我还没试过。

Answer 4

对于其他googlers：建议的解决方案不依赖于ReportLab，我们可以在我们的html模板中从其base64表示中包含条形码，因为我们已经使用另一个库创建了图像：

data_uri = open("sample.png", "rb").read().encode("base64").replace("\n", "")
# HTML Image Element
img_tag = '<img alt="" src="data:image/png;base64,{0}">'.format(data_uri)
print img_tag
# CSS Background Image
css = 'background-image: url(data:image/png;base64,{0});'.format(data_uri)
print css

Reportlab的Code128条形码作为HTML图像标签，在Python中使用数据URI方案

4 个答案: