通过遍历列表使用 python 创建 XML 文件 [英] Create XML file with python by iterating over lists

问题描述

我正在尝试获取一个看起来像这样的 xml 文件，以便我可以将其导入到 Moodle 成绩簿中:

I am trying to get an xml file that looks like this so that I can import it into a moodle gradebook:

<results>
  <result>
    <student>1</student>
    <assignment>100</assignment>
    <score>0</score>
  </result>
  <result>
    <student>1</student>
    <assignment>101</assignment>
    <score>4</score>
  </result>
  <result>
    <student>1</student>
    <assignment>102</assignment>
    <score>10</score>
  </result>
  <result>
    <student>2</student>
    <assignment>100</assignment>
    <score>0</score>
  </result>
  <result>
    <student>2</student>
    <assignment>101</assignment>
    <score>4</score>
  </result>
  <result>
    <student>2</student>
    <assignment>102</assignment>
    <score>10</score>
  </result>
</results>

我尝试用 python 编写一些代码，在仔细阅读文档后，我能想到的最好的方法是:

I have tried to write some code in python, and after poring over the documentation, the best I can come up with is:

import xml.etree.cElementTree as ET

students = [1,2]
assignments=[100,101,102]
scores=[0,4,10]
results = ET.Element("results")
result = ET.SubElement(results,"result")
student = ET.SubElement(result,"student")
assignment = ET.SubElement(result,"assignment")
score = ET.SubElement(result,"score")

for s in students:    
    for a in range(len(assignments)):
        student.text = str(s)
        assignment.text = str(assignments[a])
        score.text = str(scores[a])
        results.append(result)
tree = ET.ElementTree(results)
tree.write('test.xml')

这几乎给了我想要的东西，但最后一个条目似乎覆盖了所有以前的条目，如图所示:

This almost gives me what I want, but the last entry seems to overwrite all the previous entries as shown:

<results>
  <result>
    <student>2</student>
    <assignment>102</assignment>
    <score>10</score>
  </result>
  <result>
    <student>2</student>
    <assignment>102</assignment>
    <score>10</score>
  </result>
  <result>
    <student>2</student>
    <assignment>102</assignment>
    <score>10</score>
  </result>
  <result>
    <student>2</student>
    <assignment>102</assignment>
    <score>10</score>
  </result>
  <result>
    <student>2</student>
    <assignment>102</assignment>
    <score>10</score>
  </result>
  <result>
    <student>2</student>
    <assignment>102</assignment>
    <score>10</score>
  </result>
  <result>
    <student>2</student>
    <assignment>102</assignment>
    <score>10</score>
  </result>
</results>

我试图找到一个解决方案，但似乎大多数问题都解决了编写具有不同元素的 xml 文件的问题.我想不通的是如何使用相同的元素标签但为每个标签分配不同的值.

I have tried to find a solution, but it seems that most of the questions address just writing an xml file with distinct elements. What I can't figure out is how to use the same element tag but to assign distinct values to each one.

推荐答案

你需要做两件事:

• 将 Eli 建议的行移到 for 循环中.
• 从 for 循环中删除行:results.append(result).SubElement 工厂将父元素作为它的第一个参数(如您所知)并将新创建的实例附加父母.因此你不需要再次追加它(你不会得到任何错误，但你会得到一组与那些不同的结果您指定了).

• Move the lines Eli suggested into the for loop.
• Remove the line: results.append(result) from the for loop. The SubElement factory takes as its first argument a parent element (as you know) and it appends the newly created instance to that parent. Therefore you don't need to append it again (you won't get any error, but you will get a different set of results than the ones you specified).

你的循环应该看起来像:

You loop should then look like:

for s in students:    
    for a in range(len(assignments)):

        result = ET.SubElement(results,"result")
        student = ET.SubElement(result,"student")
        assignment = ET.SubElement(result,"assignment")
        score = ET.SubElement(result,"score")

        student.text = str(s)
        assignment.text = str(assignments[a])
        score.text = str(scores[a])

这篇关于通过遍历列表使用 python 创建 XML 文件的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！