Python技能树练习——python字符串转列表

字符串转列表"/>

Python技能树练习——python字符串转列表

一、题目与解

把下列字符串转为列表格式输出

    top_ide_trend = """
Rank	Change	IDE	Share	Trend
1		Visual Studio	29.24 %	+3.5 %
2		Eclipse	13.91 %	-2.9 %
3		Visual Studio Code	12.07 %	+3.3 %
4		Android Studio	9.13 %	-2.5 %
5		pyCharm	8.43 %	+0.7 %
6		IntelliJ	6.7 %	+0.8 %
7		NetBeans	4.82 %	-0.3 %
8		Sublime Text	3.49 %	-0.2 %
9		Xcode	3.37 %	-1.2 %
10		Atom	3.25 %	-0.5 %
11		Code::Blocks	2.16 %	+0.2 %
12		Vim	0.79 %	-0.1 %
13		Xamarin	0.48 %	-0.1 %
14		PhpStorm	0.46 %	-0.2 %
15		geany	0.39 %	+0.2 %
16		Komodo	0.31 %	-0.2 %
17		Qt Creator	0.26 %	-0.0 %
18		Emacs	0.18 %	-0.1 %
19		JDeveloper	0.13 %	-0.0 %
20		RAD Studio	0.08 %	-0.0 %
21		JCreator	0.07 %	-0.0 %
22		Light Table	0.07 %	-0.0 %
23		MonoDevelop	0.06 %	-0.0 %
24		SharpDevelop	0.03 %	-0.0 %
25		Eric Python	0.03 %	-0.0 %
26		Aptana	0.02 %	-0.0 %
27		RubyMine	0.02 %	-0.0 %
28		Coda 2	0.02 %	+0.0 %
29		Monkey Studio	0.01 %	-0.0 %
30		DrJava	0.01 %	-0.0 %
"""

输出如下：

[
{'Rank': '1', 'Change': '', 'IDE': 'Visual Studio', 'Share': '29.24 %', 'Trend': '+3.5 %'}, 
{'Rank': '2', 'Change': '', 'IDE': 'Eclipse', 'Share': '13.91 %', 'Trend': '-2.9 %'}, 
{'Rank': '3', 'Change': '', 'IDE': 'Visual Studio Code', 'Share': '12.07 %', 'Trend': '+3.3 %'}, 
{'Rank': '4', 'Change': '', 'IDE': 'Android Studio', 'Share': '9.13 %', 'Trend': '-2.5 %'}, 
{'Rank': '5', 'Change': '', 'IDE': 'pyCharm', 'Share': '8.43 %', 'Trend': '+0.7 %'}, 
{'Rank': '6', 'Change': '', 'IDE': 'IntelliJ', 'Share': '6.7 %', 'Trend': '+0.8 %'}, 
{'Rank': '7', 'Change': '', 'IDE': 'NetBeans', 'Share': '4.82 %', 'Trend': '-0.3 %'}, 
{'Rank': '8', 'Change': '', 'IDE': 'Sublime Text', 'Share': '3.49 %', 'Trend': '-0.2 %'}, 
{'Rank': '9', 'Change': '', 'IDE': 'Xcode', 'Share': '3.37 %', 'Trend': '-1.2 %'},
{'Rank': '10', 'Change': '', 'IDE': 'Atom', 'Share': '3.25 %', 'Trend': '-0.5 %'}, 
{'Rank': '11', 'Change': '', 'IDE': 'Code::Blocks', 'Share': '2.16 %', 'Trend': '+0.2 %'}, 
{'Rank': '12', 'Change': '', 'IDE': 'Vim', 'Share': '0.79 %', 'Trend': '-0.1 %'}, 
{'Rank': '13', 'Change': '', 'IDE': 'Xamarin', 'Share': '0.48 %', 'Trend': '-0.1 %'}, 
{'Rank': '14', 'Change': '', 'IDE': 'PhpStorm', 'Share': '0.46 %', 'Trend': '-0.2 %'}, 
{'Rank': '15', 'Change': '', 'IDE': 'geany', 'Share': '0.39 %', 'Trend': '+0.2 %'}, 
{'Rank': '16', 'Change': '', 'IDE': 'Komodo', 'Share': '0.31 %', 'Trend': '-0.2 %'}, 
{'Rank': '17', 'Change': '', 'IDE': 'Qt Creator', 'Share': '0.26 %', 'Trend': '-0.0 %'}, 
{'Rank': '18', 'Change': '', 'IDE': 'Emacs', 'Share': '0.18 %', 'Trend': '-0.1 %'}, 
{'Rank': '19', 'Change': '', 'IDE': 'JDeveloper', 'Share': '0.13 %', 'Trend': '-0.0 %'}, 
{'Rank': '20', 'Change': '', 'IDE': 'RAD Studio', 'Share': '0.08 %', 'Trend': '-0.0 %'}, 
{'Rank': '21', 'Change': '', 'IDE': 'JCreator', 'Share': '0.07 %', 'Trend': '-0.0 %'}, 
{'Rank': '22', 'Change': '', 'IDE': 'Light Table', 'Share': '0.07 %', 'Trend': '-0.0 %'}, 
{'Rank': '23', 'Change': '', 'IDE': 'MonoDevelop', 'Share': '0.06 %', 'Trend': '-0.0 %'}, 
{'Rank': '24', 'Change': '', 'IDE': 'SharpDevelop', 'Share': '0.03 %', 'Trend': '-0.0 %'}, 
{'Rank': '25', 'Change': '', 'IDE': 'Eric Python', 'Share': '0.03 %', 'Trend': '-0.0 %'}, 
{'Rank': '26', 'Change': '', 'IDE': 'Aptana', 'Share': '0.02 %', 'Trend': '-0.0 %'}, 
{'Rank': '27', 'Change': '', 'IDE': 'RubyMine', 'Share': '0.02 %', 'Trend': '-0.0 %'}, 
{'Rank': '28', 'Change': '', 'IDE': 'Coda 2', 'Share': '0.02 %', 'Trend': '+0.0 %'}, 
{'Rank': '29', 'Change': '', 'IDE': 'Monkey Studio', 'Share': '0.01 %', 'Trend': '-0.0 %'}, 
{'Rank': '30', 'Change': '', 'IDE': 'DrJava', 'Share': '0.01 %', 'Trend': '-0.0 %'}
]

代码如下：

def parse_ide_trend(top_ide_trend):top_ides = []top_ide_lines = top_ide_trend.split('\n')[1:]head = top_ide_lines[0]columns = head.split('\t')for row in top_ide_lines[1:]:row = row.strip()if row:cells = row.split('\t')top_ide = {}for i in range(0, len(columns)):column = columns[i]cell = cells[i]top_ide[column] = celltop_ides.append(top_ide)return top_ides if __name__ == "__main__":top_ide_trend = ...top_ides = parse_ide_trend(top_ide_trend)print(top_ides)

 二、代码理解

 2.1 直接输出看一下字符串中的格式

2.2 split("\n)

 输出结果如下：

['', 'Rank\tChange\tIDE\tShare\tTrend', '1\t\tVisual Studio\t29.24 %\t+3.5 %', '2\t\tEclipse\t13.91 %\t-2.9 %','3\t\tVisual Studio Code\t12.07 %\t+3.3 %', '4\t\tAndroid Studio\t9.13 %\t-2.5 %', '5\t\tpyCharm\t8.43 %\t+0.7 %', '']

可以看到第一个和最后一个是空值

所以对于list集合top_ide_lines，只需要取下标为1往后的值

top_ide_lines = top_ide_trend.split('\n')[1:]

由于最后一个是空，所以遍历该list时要判断非空！！

 2.3 split('\t')取表的head头数据

 2.4 遍历split('\t')取每个值数据

 只取以上划红线部分，下标为0不是值

所以需要再次用到[1:]

if __name__ == "__main__":top_ide_trend = """
Rank	Change	IDE	Share	Trend
1		Visual Studio	29.24 %	+3.5 %
2		Eclipse	13.91 %	-2.9 %
3		Visual Studio Code	12.07 %	+3.3 %
4		Android Studio	9.13 %	-2.5 %
5		pyCharm	8.43 %	+0.7 %
"""
#   top_ide_lines = top_ide_trend.split("\n")top_ide_lines = top_ide_trend.split('\n')[1:]print(top_ide_lines)head = top_ide_lines[0]columns = head.split('\t')print(columns)top_ides = []for row in top_ide_lines[1:]:row = row.strip() #删除前后空格if row: #判断非空cells = row.split('\t')top_ide = {}for item in range(0,len(columns)):column = columns[item] # item=0时，colum=Rank,作为key值cell = cells[item]  #item=0时，cell = 1，作为value值top_ide[column] = cell # item=0时，top_ide中的值为{"Rank":"1"}top_ides.append(top_ide)print(top_ides)

输出结果如下：

PS E:\myProjects\lyx> & E:/Python2/python.exe e:/myProjects/lyx/test/myPython/test.py
['Rank\tChange\tIDE\tShare\tTrend', '1\t\tVisual Studio\t29.24 %\t+3.5 %', '2\t\tEclipse\t13.91 %\t-2.9 %', '3\t\tVisual Studio Code\t12.07 %\t+3.3 %', '4\t\tAndroid Studio\t9.13 %\t-2.5 %', '5\t\tpyCharm\t8.43 %\t+0.7 %', '']
['Rank', 'Change', 'IDE', 'Share', 'Trend']
[{'Rank': '1', 'Change': '', 'IDE': 'Visual Studio', 'Share': '29.24 %', 'Trend': '+3.5 %'}, {'Rank': '2', 'Change': '', 'IDE': 'Eclipse', 'Share': '13.91 %', 'Trend': '-2.9 %'}, {'Rank': '3', 'Change': '', 'IDE': 'Visual Studio Code', 'Share': '12.07 %', 'Trend': '+3.3 %'}, {'Rank': '4', 'Change': '', 'IDE': 'Android Studio', 'Share': '9.13 %', 'Trend': '-2.5 %'}, {'Rank': '5', 'Change': '', 'IDE': 'pyCharm', 'Share': '8.43 %', 'Trend': '+0.7 %'}]
PS E:\myProjects\lyx>