如何使用 BeautifulSoup 创建带有孩子的 xml 树答案

【问题标题】：How to create an xml tree with children using BeautifulSoup如何使用 BeautifulSoup 创建带有孩子的 xml 树
【发布时间】：2020-10-10 03:09:38
【问题描述】：

这是目标

<?xml version="1.0"?>
<opencv_storage>
<intr type_id="opencv-matrix">
<rows>3</rows>
<cols>3</cols>
<dt>d</dt>
<data>
  1.4575724387217269e+03 0. 1.2129456942116219e+03 0.
  1.4575222265029629e+03 1.0073205884892100e+03 0. 0. 1.</data></intr>
</opencv_storage>

这是我的尝试

from bs4 import BeautifulSoup
soup = BeautifulSoup(features = "xml")
parent = soup.new_tag("opencv_storage")
soup.append(parent)
t = soup.parent
child_row = soup.new_tag("rows")
child_row.string = str(3)
soup.parent.insert_child(child_row)

哪个会产生错误

Traceback (most recent call last):
  File "/home/test.py", line 22, in <module>
    soup.parent.insert_child(child_row)
AttributeError: 'NoneType' object has no attribute 'insert_child'

除了告诉我如何纠正这个错误，请提供命令参考

【问题讨论】：

标签： beautifulsoup tags parent-child

【解决方案1】：

这似乎有效

from bs4 import BeautifulSoup
import numpy as np

html = '<opencv_storage><intr type_id="opencv-matrix"></opencv_storage>'
soup = BeautifulSoup(html, features = "xml")
child_row = soup.new_tag("rows")
child_row.string="3"
soup.intr.insert_after(child_row)
child_col = soup.new_tag("cols")
child_col.string="3"
soup.rows.insert_after(child_col)
child_dt = soup.new_tag("dt")
child_dt.string="d"
soup.cols.insert_after(child_dt)
arr = np.array([[1.4575724387217269e+03, 0., 1.2129456942116219e+03], 
                [0., 1.4575222265029629e+03, 1.0073205884892100e+03], 
                [0., 0., 1]])
child_data = soup.new_tag("data")
child_data.string=str(arr.flatten()).strip("[]")
soup.dt.insert_after(child_data)
print(soup.prettify())

输出

<?xml version="1.0" encoding="utf-8"?>
<opencv_storage>
 <intr type_id="opencv-matrix"/>
 <rows>
  3
 </rows>
 <cols>
  3
 </cols>
 <dt>
  d
 </dt>
 <data>
  1.45757244e+03 0.00000000e+00 1.21294569e+03 0.00000000e+00
 1.45752223e+03 1.00732059e+03 0.00000000e+00 0.00000000e+00
 1.00000000e+00
 </data>
 </opencv_storage>

【讨论】：