Python 将正确的结果传递出身份验证循环

我正在创建一个登录系统，它检索输入框中的详细信息，并将其与数据库中的详细信息进行比较。如果在数据库中找到输入的详细信息，则运行

Bottom（）

函数。如果未找到详细信息，请用户重试

目前，程序循环直到找到它。但是，由于我设置了else语句，如果数据库中的第一项不是输入的详细信息，则

else

部分仍将运行。是否有办法更改此值，以便

else

是

else

和

数据库中的最后一个值？

以下是函数：

#Retrieves the information entered into entry box
def Get_Details():
    user_namev2=user_name.get().lower() #Make it so entry box goes red if passwords password is incorrect, and red if username is incorrect/not fault
    user_passwordv2=user_password.get().lower()
    with open ('Accounts.csv', 'r') as Account_file:
        reader = csv.reader(Account_file)
        for row in reader:
            for field in row:
                if row[0] == user_namev2 and row[1] == user_passwordv2:
                    Bottom()
                    break
                else:
                    nomatch_label = Label(canvas, width = 40, height = 2, text = "USERNAME AND PASSWORD NOT FOUND", fg = "red", bg = "gray21", font = font2)
                    canvas_nomatch_label = canvas.create_window(500, 550, window = nomatch_label)
                    name_entry.config(fg = "red")
                    password_entry.config(fg="red")
                    break

---

请注意，else已被移回与for循环成对的位置

这很有希望按您所希望的方式工作，现在它在行上循环，并根据

行[0]

和

行[1]

检查用户名/密码。如果找到匹配项，它将中断并不会执行连接到for循环的else

此外，我还删除了for循环over

行

，因为无论如何都没有使用

字段

变量

#Retrieves the information entered into entry box
def Get_Details():
    user_namev2=user_name.get().lower() #Make it so entry box goes red if passwords password is incorrect, and red if username is incorrect/not fault
    user_passwordv2=user_password.get().lower()
    with open ('Accounts.csv', 'r') as Account_file:
        reader = csv.reader(Account_file)
        for row in reader:
            if row[0] == user_namev2 and row[1] == user_passwordv2:
                Bottom()
                break
        else:
            nomatch_label = Label(canvas, width = 40, height = 2, text = "USERNAME AND PASSWORD NOT FOUND", fg = "red", bg = "gray21", font = font2)
            canvas_nomatch_label = canvas.create_window(500, 550, window = nomatch_label)
            name_entry.config(fg = "red")
            password_entry.config(fg="red")

---

似乎您想要

elif

而不是

else

。是的，但是elif是什么呢？在提供正确的凭据之前让函数本身循环是没有意义的，然后才运行

Bottom（）

？此外，每次重新读取密码文件似乎效率很低。

#Retrieves the information entered into entry box
def Get_Details():
    user_namev2=user_name.get().lower() #Make it so entry box goes red if passwords password is incorrect, and red if username is incorrect/not fault
    user_passwordv2=user_password.get().lower()
    with open ('Accounts.csv', 'r') as Account_file:
        reader = csv.reader(Account_file)
        for row in reader:
            if row[0] == user_namev2 and row[1] == user_passwordv2:
                Bottom()
                break
        else:
            nomatch_label = Label(canvas, width = 40, height = 2, text = "USERNAME AND PASSWORD NOT FOUND", fg = "red", bg = "gray21", font = font2)
            canvas_nomatch_label = canvas.create_window(500, 550, window = nomatch_label)
            name_entry.config(fg = "red")
            password_entry.config(fg="red")