Tkinter在搜索中没有ascii错误

Question

我试图在Tkinter中实现搜索。一切都运行完美而不list_box元素非ASCII字符（用于填充列表框列表变量然而，在搜索输入非ASCII字符返回错误：

Exception in Tkinter callback 
Traceback (most recent call last): 
    File "/usr/lib/python2.7/lib-tk/Tkinter.py", line 1489, in __call__ 
    return self.func(*args) 
    File "ex2_af.py", line 20, in <lambda> 
    self.search_var.trace("w", lambda name, index, mode: self.update_list()) 
    File "ex2_af.py", line 41, in update_list 
    if search_term.lower() in item.lower(): 
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc5 in position 0: ordinal not in range(128) 

下面是代码：

# -*- coding: utf-8 -*- 
from Tkinter import * 
# First create application class 
class Application(Frame): 
    def __init__(self, master=None): 
     Frame.__init__(self, master) 
     self.pack() 
     self.create_widgets() 
    # Create main GUI window 
    def create_widgets(self): 
     self.search_var = StringVar() 
     self.search_var.trace("w", lambda name, index, mode: self.update_list()) 
     self.entry = Entry(self, textvariable=self.search_var, width=13) 
     self.lbox = Listbox(self, width=45, height=15) 
     self.entry.grid(row=0, column=0, padx=10, pady=3) 
     self.lbox.grid(row=1, column=0, padx=10, pady=3) 
     # Function for updating the list/doing the search. 
     # It needs to be called here to populate the listbox. 
     self.update_list() 
    def update_list(self): 
     search_term = self.search_var.get() 
     # Last element, 'Čelo' represents non-ascii part. 
     # You may add any non-ascii to see what I'm talking about. 
     # How to access this element? 
     lbox_list = ['Adam', 'Lucy', 'Barry', 'Bob', 
     'James', 'Frank', 'Susan', 'Amanda', 'Christie', 'Čelo'] 
     self.lbox.delete(0, END) 
     for item in lbox_list: 
      if search_term.lower() in item.lower(): 
       self.lbox.insert(END, item) 
root = Tk() 
app = Application(master=root) 
app.mainloop() 

Answer 1

比较str和unicode（用户输入）（该lbox_list的项目）隐含尝试使用默认编码str对象转换为unicode（ASCII，除非另有配置）。

>>> u'Čelo' in 'Čelo' 
Traceback (most recent call last): 
    File "<stdin>", line 1, in <module> 
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc4 in position 0: ordinal not in range(128) 
>>> u'Čelo' in u'Čelo' 
True 

您可以通过避免这样的隐式解码通过定义列表作为统一码清单解决问题：

lbox_list = [               
    u'Adam', u'Lucy', u'Barry', u'Bob', 
    u'James', u'Frank', u'Susan', u'Amanda', u'Christie', 
    u'Čelo' 
]