从 Tkinter，我如何将字符串转换为整数以用于潜在的随机密码生成器

Question

So I'm trying to create a GUI, i think, where it creates a random password. the number that is typed in the entry box will determine the amount of digits the password will have. Example: the number 12 will be a 12 digit password. I'm having trouble with making the number into an integer value where i can then use it for the random password function. The function 'generate' cant generate a random password and i dont know why.

here is the code

import random
import string
import tkinter

root = tkinter.Tk()

root.title('Random Password generator')
root.geometry("200x200")

def generatepassword():
    password =''
    for a in range(num):
        a = random.randint(1, 50)
        password += string.printable[a]
    return password


def generate():
    new_number = Entry1.get()
    generate_text = tkinter.Label(root, text="Password is: " + generatepassword(new_number))
    generate_text.pack()


Message = tkinter.Label(root, text="Enter an number:").pack()

Entry1 = tkinter.Entry(root, font="calibra")
Entry1.pack()

Button = tkinter.Button(root, height=1, width=6, text='Submit', command=generate).pack()

root.mainloop()

Answer 1

The Entry1.get() method will always return a string. If you want to use it as a integer or a float you will need to cast it before you do so. The built in int() function is one of your options.

  new_number = int(Entry1.get())

Answer 2

Because get() will always return a string from an Entry field you need to have some way to make use when you use int() that the value is actually an integer. The quick and easy way is to use a try/except statement. That said there are a few things I would change.

1st. We do not need 2 functions here. Everything can be done in one function.

2nd. Updated your code to follow PEP8 a bit more closely.

3rd. added a focus() and bind() to make this more user friendly.

4th. Moved the label for passwords to be created in the global namespace and changed it so we are only updating the password instead of adding new lines.

Lastly I added a try/except statement so we can handle the case if someone tries to submit a non-int as well as added in the missing argument and a conversion to integer.

See below code and let me know if you have any questions.

import tkinter as tk
import random
import string


def generate_password():
    try:
        password = ''
        for _ in range(int(entry1.get())):
            a = random.randint(1, 50)
            password = '{}{}'.format(password, string.printable[a])
        generate_text.config(text="Password is: {}".format(password))
    except BaseException as e:
        print('{}'.format(e))


root = tk.Tk()
root.title('Random Password generator')
root.geometry("200x200")

message = tk.Label(root, text="Enter an number:")
entry1 = tk.Entry(root, font="calibra")
button = tk.Button(root, height=1, width=6, text='Submit', command=generate_password)
generate_text = tk.Label(root, text="")

message.pack()
entry1.pack()
button.pack()
generate_text.pack()

entry1.focus()
entry1.bind('<Return>', generate_password)

root.mainloop()

Answer 3

Use IntVar() to accept an integer directly.

Since you want a all digits password, this code just does that.

Code:

import random
import string
import tkinter as tk

root = tk.Tk()

root.title('Random Password generator')

message = tk.Label(root, text="Enter an number:")
message.pack()

# take an integer input rather than a string
number = tk.IntVar()
entry1 = tk.Entry(root, font="calibra", textvariable=number)
entry1.pack()

def generatepassword(number):
    password = ''
    for i in range(number):
        # randint is inclusive at both ends
        digit = random.randint(0, 9)
        password += str(digit)
    return password

generate_text = tk.Label(root)
generate_text.pack()

def generate():
    pwd_len = number.get()
    password = generatepassword(pwd_len)
    generate_text.config(text="Password is: " + password)

button = tk.Button(root, height=1, width=6, text='Submit', command=generate)
button.pack()

root.mainloop()

NOTE: IntVar() has a default value of 0 , you can enter any number in place of 0 and have your password.

Output:

Also, if you want a password that has both alphabets (uppercase & lowercase) and digits, replace the generatepassword() function with the following version:

def generatepassword(number):
    password = ''
    for i in range(number):
        password += random.choice(string.ascii_letters + string.digits)  
    return password