二进制/十进制/十六进制转换创建无类型输出输出

Question

我正在创建一个代码，使用tkinter，在二进制、十进制和十六进制之间进行转换。它不会产生错误，但是在输出框中，它会产生字符串“None”。我不知道这是为什么，因为当我尝试使用空闲I/O功能（input和print）的转换代码时，它工作得非常好。这是我的密码：

from tkinter import *


def conversion(number, mode, outmode):
    global out
    if mode == 'hex':
        if outmode == 'hex':
            out = number

        elif outmode == 'dec':
            out = int(number, 16)

        else:
            number = int(number, 16)
            out = bin(number)

    elif mode == 'dec':

        number = int(number)

        if outmode == 'hex':
            out = hex(number)

        elif outmode == 'dec':
            out = number

        else:
            out = bin(number)

    else:
        if outmode == 'hex':
            number = int(number, 2)
            out = hex(number)

        elif outmode == 'dec':
            out = int(number, 2)

        else:
            out = number


# Key Press Functions
def click():
    entered_number = entry.get() # Collect number from text box
    output.delete(0.0, END) # Clear text box
    global out
    out = conversion(entered_number, mode, outmode)
    out = str(out)
    output.insert(END, out)

def hex_in():
    global mode

    if hex_btn_in.config('relief')[-1] == 'sunken':
        hex_btn_in.config(relief='raised')

    else:
        hex_btn_in.config(relief='sunken')
        dec_btn_in.config(relief='raised')
        bin_btn_in.config(relief='raised')
        hex_btn_out.config(relief='raised')
        mode = 'hex'

def dec_in():
    global mode

    if dec_btn_in.config('relief')[-1] == 'sunken':
        dec_btn_in.config(relief='raised')

    else:
        dec_btn_in.config(relief='sunken')
        bin_btn_in.config(relief='raised')
        hex_btn_in.config(relief='raised')
        dec_btn_out.config(relief='raised')
        mode = 'dec'

def bin_in():
    global mode

    if bin_btn_in.config('relief')[-1] == 'sunken':
        bin_btn_in.config(relief='raised')

    else:
        bin_btn_in.config(relief='sunken')
        dec_btn_in.config(relief='raised')
        hex_btn_in.config(relief='raised')
        bin_btn_out.config(relief='raised')
        mode = 'bin'

def hex_out():
    global outmode

    if hex_btn_out.config('relief')[-1] == 'sunken':
        hex_btn_out.config(relief='raised')

    else:
        hex_btn_out.config(relief='sunken')
        dec_btn_out.config(relief='raised')
        bin_btn_out.config(relief='raised')
        outmode = 'hex'

    if hex_btn_in.config('relief')[-1] == 'sunken':
        hex_btn_out.config(relief='raised')

def dec_out():
    global outmode

    if dec_btn_out.config('relief')[-1] == 'sunken':
        dec_btn_out.config(relief='raised')

    else:
        dec_btn_out.config(relief='sunken')
        bin_btn_out.config(relief='raised')
        hex_btn_out.config(relief='raised')
        outmode = 'dec'

    if dec_btn_in.config('relief')[-1] == 'sunken':
        dec_btn_out.config(relief='raised')

def bin_out():
    global outmode

    if bin_btn_out.config('relief')[-1] == 'sunken':
        bin_btn_out.config(relief='raised')

    else:
        bin_btn_out.config(relief='sunken')
        dec_btn_out.config(relief='raised')
        hex_btn_out.config(relief='raised')
        outmode = 'bin'

    if bin_btn_in.config('relief')[-1] == 'sunken':
        bin_btn_out.config(relief='raised')

## Main:
window = Tk()
window.title('Hexadecimal/Decimal/Binary Converter')

# Create labels
Label(window, text='Enter the input mode:').grid(row=0, column=0, sticky=W)
Label(window, text='Enter your number:').grid(row=2, column=0, sticky=W)
Label(window, text='Enter your output mode:').grid(row=5, column=0, sticky=W)
Label(window, text='Output:').grid(row=7, column=0, sticky=W)

# Create number entry box
entry = Entry(window, width=20, bg='light green')
entry.grid(row=3, column=0, sticky=W)

# Add input boxes: hex, bin, dec
hex_btn_in = Button(text='Hexadecimal', width=12, relief='raised', command=hex_in)
hex_btn_in.grid(row=1, column=0, sticky=W)

dec_btn_in = Button(text='Decimal', width=12, relief='raised', command=dec_in)
dec_btn_in.grid(row=1, column=1, sticky=W)

bin_btn_in = Button(text='Binary', width=12, relief='raised', command=bin_in)
bin_btn_in.grid(row=1, column=2, sticky=W)

# Add output boxes: hex, bin, dec
hex_btn_out = Button(text='Hexadecimal', width=12, relief='raised', command=hex_out)
hex_btn_out.grid(row=6, column=0, sticky=W)

dec_btn_out = Button(text='Decimal', width=12, relief='raised', command=dec_out)
dec_btn_out.grid(row=6, column=1, sticky=W)

bin_btn_out = Button(text='Binary', width=12, relief='raised', command=bin_out)
bin_btn_out.grid(row=6, column=2, sticky=W)

# Add a submit button
Button(window, text='Submit', width=5, command=click).grid(row=4, column=0, sticky=W)

# Create a text box for output
output = Text(window, width=36, height=6, wrap=WORD, bg='light green')
output.grid(row=8, column=0, columnspan=2, sticky=W)

## Run mainloop:
window.mainloop()

结果如下： Binary, Hexadecimal and Decimal Converter output

如果有人能解释为什么要创建这个输出和/或如何修复它，我们将不胜感激。你知道吗

Answer 1

转换函数赋值给全局变量out，不返回任何内容（因此它隐式返回None）。您应该将out = conversion(entered_number, mode, outmode)行更改为conversion(entered_number, mode, outmode)