__init__() 缺少 1 个必需的位置参数：“接收器”？

Question

Im trying to get the data of a word through database with sqlite3 and python but when i try to call the read_from_db function, i have this error _init__() missing 1 required positional argument: 'receiver'. I cant seem to find what happened
heres the code

conn = sqlite3.connect('yeet1.db')
cursor = conn.cursor()


class Ui_WordWindow(object):


    def __init__(self, receiver):  #Inherit user-input word from another window

        self.receiver = receiver        
        print(self.receiver) #Checking if it worked correctly

    def read_From_db(self): #Read and print out data of user-input word

         cursor.execute(('SELECT * FROM mytable WHERE Meaning = ?', self.receiver))
         data = cursor.fetchall()
         print(data)




window2 = Ui_WordWindow()
window2.read_From_db()
cursor.close()
conn.close

Answer 1

You declare the __init__ method of the class Ui_WordWindow like so:

def __init__(self, receiver):  #Inherit user-input word from another window

And it does have a parameter receiver. The error you get indicates that when constructing a Ui_WordWindow you should provide exactly one parameter and that should be the value for receiver.

Ie this line:

window2 = Ui_WordWindow()

Should in fact be:

window2 = Ui_WordWindow(receiver)

where receiver is a valid value for receiver.

Answer 2

The receiver object = "some value"

conn = sqlite3.connect('yeet1.db')
cursor = conn.cursor()


class Ui_WordWindow(object):


    def __init__(self, receiver):  #Inherit user-input word from another window

        self.receiver = receiver        
        print(self.receiver) #Checking if it worked correctly
        #when you print self.receiver it means the value which you are passing say for example "test"  

    def read_From_db(self): #Read and print out data of user-input word

         cursor.execute(('SELECT * FROM mytable WHERE Meaning = ?', "test"))

         # now the query becomes select * from mytable where meaning = 'test'
         # the value 'test' is being passed by the receiver object and you need to provide that value

         data = cursor.fetchall()
         print(data)




window2 = Ui_WordWindow(receiver) # which has some value ex 'test'
window2.read_From_db()
cursor.close()
conn.close

you need to brush up on object oriented approach. try reading from this: python object oriented