不能從一種方法返回布爾值

Question

我有一個方法，我檢查用戶是否存在於數據庫中，我想將該方法結果傳遞給另一個方法，但無法這樣做，錯誤我看到的是「類型錯誤：‘布爾’對象不是可調用的」

這裏是我的代碼：

def userInDb(username, email, password): 
    cursor = mysql.get_db().cursor() 
    cursor.execute('SELECT userID from user WHERE userName = %s and email = %s and password = %s', [username, email, password]) 
    data = cursor.fetchone() 

    if data is None: 
     return False 
    else: 
     True 

而這正是我試圖調用aboves方法結果

@app.route('/showSignIn', methods=["POST"]) 
def showSignInPost(): 
    username = request.form['inputUserName'] # values received from the UI input by users 
    email = request.form['inputEmail'] 
    password = request.form['inputPassword'] 

    inDB == userInDb(username, email, password) 

    if inDB is True: 
     return render_template('signin.html', signInHeader = "User doesn't exist, please try again") 
    else: 
     return render_template('signin.html', signInHeader = "Welcome " + username) 

非常感謝即

Answer 1

你忘記返回True

def userInDb(username, email, password): 
    cursor = mysql.get_db().cursor() 
    cursor.execute('SELECT userID from user WHERE userName = %s and email = %s and password = %s', [username, email, password]) 
    data = cursor.fetchone() 

    if data is None: 
     return False 
    else: 
     return True #you forgot return 

你正在測試inDB == userInDb(...)而不是分配inDB = userInDb(...)

你也可以做if inDB:代替if inDB is True:

如果你這樣做

def userInDb(username, email, password): 
    cursor = mysql.get_db().cursor() 
    cursor.execute('SELECT userID from user WHERE userName = %s and email = %s and password = %s', [username, email, password]) 
    data = cursor.fetchone() 

    return bool(data) # just return bool of data 

將會更清潔