从tkvar.get()截断字典
从tkvar.get()截断字典
提问于 2018-07-07 04:19:39
我已经创建了一个带有两个下拉菜单的Tkinter窗口，允许用户选择开始月份和结束月份来计算设定范围内的数据(见下文)：
from tkinter import *
from pandas import Timestamp
root = Tk()
root.title("Select your Month Range")
# Setting up Grid
mainframe = Frame(root)
mainframe.pack(pady=50, padx=50)
Label(mainframe, text="Select Start Month").grid(row=1, column=1)
Label(mainframe, text="Select End Month").grid(row=1, column=6)
# Creating two Tkinter variables to obtain user input from the drop down menus
tkvar_start = StringVar(root)
tkvar_end = StringVar(root)
tkvar_start.set('Jan 17') # Setting a default option
tkvar_end.set(endDate)
start_popupMenu = OptionMenu(mainframe, tkvar_start, *dict_months)
end_popupMenu = OptionMenu(mainframe, tkvar_end, *dict_months)
start_popupMenu.grid(row=2, column=1)
end_popupMenu.grid(row=2, column=6)
def callback_range():
print('The range is from %s to %s' % (tkvar_start.get(), tkvar_end.get()))
#range_dict_months = dict(itertools.islice(dict_months.items(), 3))
button = Button(mainframe, text = "OK", command = callback_range)
button.grid(row=3, column=23)上面的代码生成了这个窗口，除了默认选项是7月18日而不是3月，我在测试代码后截取了我的窗口的屏幕截图：
我的两个弹出菜单字典dict_months是：
>>> dict_months
{'Jan 17': Timestamp('2017-01-01 00:00:00'),
'Feb 17': Timestamp('2017-02-01 00:00:00'),
'Mar 17': Timestamp('2017-03-01 00:00:00'),
'Apr 17': Timestamp('2017-04-01 00:00:00'),
'May 17': Timestamp('2017-05-01 00:00:00'),
'Jun 17': Timestamp('2017-06-01 00:00:00'),
'Jul 17': Timestamp('2017-07-01 00:00:00'),
'Aug 17': Timestamp('2017-08-01 00:00:00'),
'Sep 17': Timestamp('2017-09-01 00:00:00'),
'Oct 17': Timestamp('2017-10-01 00:00:00'),
'Nov 17': Timestamp('2017-11-01 00:00:00'),
'Dec 17': Timestamp('2017-12-01 00:00:00'),
'Jan 18': Timestamp('2018-01-01 00:00:00'),
'Feb 18': Timestamp('2018-02-01 00:00:00'),
'Mar 18': Timestamp('2018-03-01 00:00:00'),
'Apr 18': Timestamp('2018-04-01 00:00:00'),
'May 18': Timestamp('2018-05-01 00:00:00'),
'Jun 18': Timestamp('2018-06-01 00:00:00'),
'Jul 18': Timestamp('2018-07-01 00:00:00')}我想修改我的 callback_range() 函数，以包括截断/切分用户输入的字典。例如，如果用户选择Jan 17到Mar 17，如图所示，则所需输出应为：
>>> dict
{'Jan 17': Timestamp('2017-01-01 00:00:00'),
'Feb 17': Timestamp('2017-02-01 00:00:00'),
'Mar 17': Timestamp('2017-03-01 00:00:00')}如何使用tkvar_start.get()和tkvar_end.get()截断字典，并包括字典之间的月份？字典是不可迭代的，我可能是错的，但是使用iterslice似乎需要使用索引。
islice(sequence, start, stop, step)
回答 1
Stack Overflow用户
回答已采纳
发布于 2018-07-07 08:19:51
嗯，这可能不是最好的方法，但你可以这样做：
def callback_range():
list_of_keys = list(dict_months.keys())
# approach 1
range_dict = { k:dict_months[k] for k in list_of_keys[list_of_keys.index(tkvar_start.get()):list_of_keys.index(tkvar_end.get())+1]}
print(range_dict)
# approach 2
import itertools
range_dict = dict(itertools.islice(dict_months.items(),list_of_keys.index(tkvar_start.get()), list_of_keys.index(tkvar_end.get())+1))
print(range_dict)输出：
{'Jan 17': Timestamp('2017-01-01 00:00:00'), 'Feb 17': Timestamp('2017-02-01 00:00:00'), 'Mar 17': Timestamp('2017-03-01 00:00:00')}
{'Jan 17': Timestamp('2017-01-01 00:00:00'), 'Feb 17': Timestamp('2017-02-01 00:00:00'), 'Mar 17': Timestamp('2017-03-01 00:00:00')}页面原文内容由Stack Overflow提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接：
https://stackoverflow.com/questions/51217104
复制相关文章
相似问题