how to create a login form in python how i can check if username and password is present in the database? this is my code

[A Former User]

import sys
import os
import mysql.connector
from PyQt4.QtGui import *
from PyQt4.QtCore import *

class Form(QDialog):
    def __init__(self, parent=None):
        super(Form,self).__init__(parent)

        self.username = QLineEdit(self)
        self.QUserLabel = QLabel("USERNAME")

        self.password = QLineEdit(self)
        self.QPasswordLabel = QLabel("PASSWORD")

        self.btn_Submit = QPushButton("LOGIN")

        layout = QFormLayout()
        layout.addRow(self.QUserLabel,self.username)
        layout.addRow(self.QPasswordLabel,self.password)
        layout.addRow(self.btn_Submit)

        self.setLayout(layout)

        self.connect(self.btn_Submit, SIGNAL("clicked()"),self.Submit_btn)

    def Submit_btn(self):
        USERNAME = self.username.text()
        PASSWORD = self.password.text()
        
        con = mysql.connector.connect(user="root",password="admingelo",host="localhost",database="user")
        manager = con.cursor()

        get_query = ("""SELECT username,password FROM users WHERE username = '%s' AND password = '%s' """%str(USERNAME,PASSWORD))
        manager.execute(get_query)
        print get_query
        con.commit()

        if self.username.text() == USERNAME and self.password.text() == PASSWORD:
            print "hello"
        else:
            print "nothing match"
        
app = QApplication(sys.argv)
form = Form()
form.show()
app.exec_()

get_query = ("""SELECT username,password FROM users WHERE username = '%s' AND password = '%s' """%str(USERNAME,PASSWORD))
TypeError: str() takes at most 1 argument (2 given)

[p3c0]

@Gelo According to python documentation str() takes single argument but you have passed 2.

[A Former User]

@p3c0 this is my latest code

import sys
import os
import mysql.connector
from PyQt4.QtGui import *
from PyQt4.QtCore import *
from PyQt4.QtSql import *

class Form(QDialog):
    def __init__(self, parent=None):
        super(Form,self).__init__(parent)

        self.username = QLineEdit(self)
        self.QUserLabel = QLabel("USERNAME")

        self.password = QLineEdit(self)
        self.QPasswordLabel = QLabel("PASSWORD")

        self.btn_Submit = QPushButton("LOGIN")

        layout = QFormLayout()
        layout.addRow(self.QUserLabel,self.username)
        layout.addRow(self.QPasswordLabel,self.password)
        layout.addRow(self.btn_Submit)

        self.setLayout(layout)

        self.connect(self.btn_Submit, SIGNAL("clicked()"),self.Submit_btn)

    def Submit_btn(self):
        USERNAME = self.username.text()
        PASSWORD = self.password.text()
        
        con = mysql.connector.connect(user="root",password="admingelo",host="localhost",database="user")
        manager = con.cursor()

        get_username = ("SELECT username FROM users WHERE username = '%s'"%str(USERNAME))
        get_password = ("SELECT password FROM users WHERE password = '%s'"%str(PASSWORD))
        manager.execute(get_username,get_password)
        print get_username
        print get_password
        #con.commit()

        if self.username.text() == get_username and self.password.text() == get_password:
            print "ah"
        else:
            print "nothing"
        
app = QApplication(sys.argv)
form = Form()
form.show()
app.exec_()

[p3c0]

@Gelo Great so was that the exact cause ?

[A Former User]

@p3c0 it just print this instead to check if what i enter do exist

RESTART: C:/Users/angelo/Desktop/IMS Delta EarthMoving Incorporated/QtLogin.py
SELECT username FROM users WHERE username = 'admin'
SELECT password FROM users WHERE password = 'password'

[A Former User]

@p3c0 i want my script to check if what i enter is on database then if not it will print nothing or query not exist

[p3c0]

@Gelo Sorry I'm not much aware of PyQt but here is an example:
http://www.codeprogress.com/python/libraries/pyqt/showPyQTExample.php?index=422&key=QSqlDatabaseConnecttoMySql

db 	= QSqlDatabase.addDatabase("QMYSQL")
db.setHostName("10.30.0.30")
db.setDatabaseName("testDB")
db.setUserName("root")
db.setPassword("password")

query = QSqlQuery ("SELECT * FROM test") 
while (query.next()):
    data = query.value(0).toString()

You can try doing in the similar terms.

[A Former User]

@p3c0 Thank you for your help i already solve the problem :)

[p3c0]

@Gelo Congratulations :) You can post the updated rectified code so that it might be helpful for others in the future.

[A Former User]

@p3c0 Yeah sure :) Thank you my friend!

[p3c0]

Updated working code by @Gelo :

import sys
import os
import mysql.connector
from PyQt4.QtGui import *
from PyQt4.QtCore import *
from PyQt4.QtSql import *

class Form(QDialog):
    def __init__(self, parent=None):
        super(Form,self).__init__(parent)

        self.db = QSqlDatabase.addDatabase("QMYSQL")
        self.db.setHostName("localhost")
        self.db.setDatabaseName("user")
        self.db.setUserName("root")
        self.db.setPassword("admingelo")
        self.db.open()

        self.username = QLineEdit(self)
        self.QUserLabel = QLabel("USERNAME")

        self.password = QLineEdit(self)
        self.QPasswordLabel = QLabel("PASSWORD")
        self.password.setEchoMode(QLineEdit.Password)

        self.btn_Submit = QPushButton("LOGIN")

        layout = QFormLayout()
        layout.addRow(self.QUserLabel,self.username)
        layout.addRow(self.QPasswordLabel,self.password)
        layout.addRow(self.btn_Submit)

        self.setLayout(layout)

        self.connect(self.btn_Submit, SIGNAL("clicked()"),self.Submit_btn)

    def Submit_btn(self):
        USERNAME = self.username.text()
        PASSWORD = self.password.text()

        self.query = QSqlQuery("SELECT username,password FROM users")
        while (self.query.next()):
            username = self.query.value(0).toString()
            password = self.query.value(1).toString()

        if USERNAME == username and PASSWORD == password:
            print "Login!"
        else:
            print "failed"

        
app = QApplication(sys.argv)
form = Form()
form.show()
app.exec_()

[jayrawatrj]

self.connect(self.btn_Submit, SIGNAL("clicked()"),self.Submit_btn)

what is "SIGNAL" here,??

[SGaist]

Hi and welcome to devnet,

Please take a look at the new syntax documentation.

[jayrawatrj]

thanks or reply.. instead of SIGNAL now we are using pyqtSignal() but here SIGNAL("clicked()") instead of clicked() what should i pass cause clicked () is giving error as

""self.btn_Submit.clicked.connect(pyqtSignal('clicked'),self.Submit_btn)

TypeError: C++ type 'clicked' is not supported as a pyqtSignal() type argument type ""

[SGaist]

Did you read PyQt's New-style Signal and Slot Support ?