无法调用openfile函数

Question

我正试图通过菜单栏打开一个文件。但是，它总是给我这个错误“TypeError:unbound method openfile（）must be called with hash instance as first argument（got nothing instead）”我以前从未遇到过这个错误，所以我不知道该怎么办。我正在使用Tkinter作为我的GUI。你知道吗

 class application:
    def openfile():
        filename = askopenfilename(parent=root)
        f = open(filename)
        f.read()
        print (filename)

    def hashmd5():
        BLOCKSIZE = 65536
        hasher = hashlib.md5()
        with open(askopenfilename(), 'rb') as afile:
            buf = afile.read(BLOCKSIZE)
            while len(buf) > 0:
                hasher.update(buf)
                buf = afile.read(BLOCKSIZE)
                print(hasher.hexdigest())

menubar = Menu(root)
filemenu = Menu(menubar, tearoff=0)
filemenu.add_command(label="Save", command=filemenu)
filemenu.add_command(label="Open", command=hash.openfile)
filemenu.add_separator()
filemenu.add_command(label="Exit", command=root.quit)
menubar.add_cascade(label="File", menu=filemenu)

更新： 我设法解决了我的代码错误，它的工作很好，但当我试图添加一个登录窗口使用标签和按钮，窗口没有出现在所有。你知道吗

import hashlib
import Tkinter as tk
from tkFileDialog import askopenfilename

class Application(object):

def __init__(self):
    self.root = root = tk.Tk()
    menubar = tk.Menu(root)
    root.title("Hashing Tool")
    root.geometry("300x150")

    filemenu = tk.Menu(menubar, tearoff=0)
    filemenu.add_command(label="Hash", command=self.hashmd5)
    filemenu.add_command(label="Exit", command=root.quit)

    menubar.add_cascade(label="File", menu=filemenu)
    root.config(menu=menubar)


    self.filename = tk.StringVar()
    self.filename.set("No File Selected")
    lbl = tk.Label(root, textvariable=self.filename, anchor="w")
    lbl.pack()


    self.digest = tk.StringVar()
    lbl = tk.Label(root, textvariable=self.digest, anchor="w")
    lbl.pack()

def create_widgets(self):
        self.instruction = Label(self ,text ="enter")
        self.instruction.grid(row = 0,column = 0, columnspan = 2,sticky =W)


        self.password = Entry(self)
        self.password.grid(row = 1, column = 1, sticky = W)

        self.submit_button = Button (self ,text = "submit")
        self.submit_button.grid(row = 2, column = 0, sticky = W)

        self.text = Text(self,width = 35, height = 5, wrap = WORD)

def reveal(self):
        cotent = self.password.get()

        if content == "password":
            message = "Accessed"
        else:message = "Denied"

        self.text.insert(0,0,message)

        root.mainloop()


def hashmd5(self):
    BLOCKSIZE = 65536
    hasher = hashlib.md5()
    filename = askopenfilename(parent=self.root)
    self.filename.set(filename)
    print(filename)

    with open(filename, 'rb') as afile:
        buf = afile.read(BLOCKSIZE)
        while len(buf) > 0:
            hasher.update(buf)
            buf = afile.read(BLOCKSIZE)
            digest = hasher.hexdigest()
            self.digest.set(digest)
            print(digest)

Application()

Answer 1

有多种方法可以组织代码。有一种方法：

import hashlib
import Tkinter as tk
from tkFileDialog import askopenfilename

class Application(object):
    def __init__(self):
        self.root = root = tk.Tk()
        menubar = tk.Menu(root)

        filemenu = tk.Menu(menubar, tearoff=0)
        filemenu.add_command(label="Hash", command=self.hashmd5)
        filemenu.add_command(label="Exit", command=root.quit)

        menubar.add_cascade(label="File", menu=filemenu)
        root.config(menu=menubar)

        #Add a Label to hold the current filename
        self.filename = tk.StringVar()
        self.filename.set("No File Selected")
        lbl = tk.Label(root, textvariable=self.filename, anchor="w")
        lbl.pack()

        #Add a Label to hold the most recent MD5 digest
        self.digest = tk.StringVar()
        lbl = tk.Label(root, textvariable=self.digest, anchor="w")
        lbl.pack()

        root.mainloop()

    def hashmd5(self):
        BLOCKSIZE = 65536
        hasher = hashlib.md5()
        filename = askopenfilename(parent=self.root)
        self.filename.set(filename)
        print(filename)

        with open(filename, 'rb') as afile:
            buf = afile.read(BLOCKSIZE)
            while len(buf) > 0:
                hasher.update(buf)
                buf = afile.read(BLOCKSIZE)
                digest = hasher.hexdigest()
                self.digest.set(digest)
                print(digest)

Application()

如果您在python3上运行这个命令，您需要更改Tkinter import语句。你知道吗

Answer 2

类方法要求它们的第一个参数是self，并且必须在类的实例上调用。你知道吗

如果您试图创建静态方法（在类本身上调用），那么应该在方法定义之前加上@staticmethod。你知道吗

例如

class hash:
    @staticmethod
    def openfile():
        # ...