如何检查Tkinter中的输入框是否为空?
换句话说,它是否没有分配值。
您可以获取该值,然后检查其长度:
if len(the_entry_widget.get()) == 0:
do_something()
您可以获取小部件中最后一个字符的索引。如果最后的索引是0(零),则为空:if the_entry_widget.index("end") == 0:
do_something()
StringVar()
,请使用以下代码:v = StringVar()
entry = Entry(root, textvariable=v)
if not v.get():
#do something
entry = Entry(root)
if not entry.get():
#do something
if not the_entry_widget.get():
#do something
import Tkinter as tk
#import tkinter as tk (Python 3.4)
class App:
#Initialization
def __init__(self, window):
#Set the var type for your entry
self.entry_var = tk.StringVar()
self.entry_widget = tk.Entry(window, textvariable=self.entry_var).pack()
self.button = tk.Button(window, text='Test', command=self.check).pack()
def check(self):
#Retrieve the value from the entry and store it to a variable
var = self.entry_var.get()
if var == '':
print "The value is not valid"
else:
print "The value is valid"
root = tk.Tk()
obj = App(root)
root.mainloop()
上面的输入只能包含数字和字符串。如果用户输入了空格,则会输出错误消息。现在,如果你想让输入以整数、浮点数或其他形式呈现,你只需要进行强制转换!
Example:
yourVar = '5'
newVar = float(yourVar)
>>> 5.0