Pyhton Programming

Programs to Read and Write Files

#program to read files

f=open("abc.txt",'r')

f.read()

f.close

#program for writing files

f=open("abc.txt",'w')

f.write("HEllO WOrld")

f.close

#programs based on read and write files

a=open("text.txt","w")

a.write(“welcome to python”)

a.write(“This my first line\n”)

a.write(“This is my second line\n”)

a.write(“This is third line\n”)

a.close()

#Program to write lines of text 

Obj=open(“text.txt”,”w”)

Lot=[“Python is the software “,”\n which is used for create and run the program “,”\n Python programming language”]

Obj.writelines(Lot)

Obj.close() 

#Create a program to first check to see if the file name is exist .So if it will give an error massage if it will not create the file 

import os

def create_file()

        if os.path.isfile(“text.txt”):

             print(“file already exists”)

        else:

              f=open(“text.txt”,”w”)

              f.write(“create a new text file”)

              f.close()

create_file()

#write a python program to read an entire text file.

def file_read(fname):

    txt = open(fname)

    print(txt.read())

file_read("text.txt")

#write a python program to append text to a file and display the text

def file_read(fname):

    from itertools import islice

    with open(fname,"w")as myfile:

        myfile.write("python exercise\t")

        myfile.write("Java exercise\t")

    txt=open(fname)

    print(txt.read())

file_read("abc.txt")   

Programs to demonstrate exception handling

#Demonstrate Exception.

try:

  fh = open("fycs.txt", "w")

  fh.write("This is my test file for exception handling!!")

finally:

  print ("Error: can\'t find file or read data")

#Open a file and write  the file comes out Gracefully.

try:

   fh = open("fycs7.txt", "r+")

   fh.write("This is my test file for exception handling!!")

except IOError:

   print ("Error: can\'t find file or read data" )

else:

   print ("Written content in the file successfully")

#Program to take input and print integer is Valid or Not.

while True:

  try:

    n=int(input("Enter an integer: "))    

  except ValueError:

      print("You have entered Wrong integer.")

  else:

      print("You have entered Valid integer.")

Programs to demonstrate use of regular expressions

Below program must be executed in python shell

Import re

Print(re.split(r’ \s*’,’my first RE program’))

Import re

Print(re.split(r’[a-e]’,’my beautiful daughter’))

Import  re

Print(‘\nfind the digits’)

Print(re.findall(r’ \d’,’meera 18927 road’))
Print (‘n\find the non-digits’)

Print(re.findall(r’\D’,’meera 18927 road’))

Print(‘\nfind the non-space’)

Print(re.findall(r’\s’,’meera 18927 road’))

Import  re

Print(‘\nfind the digits’)

Print(re.findall(r’\d{1,3}\s\w+’,’meera 18927 road’))

Programs to show draw shapes and GUI controls

#create line with rectangle

from tkinter import*

root=Tk()

w=Canvas(root,width=200,height=100,bg="red")

w.pack()

w.create_line(0,0,200,100)

w.create_line(0,100,200,0,fill="red",dash=(4,4))

w.create_rectangle(50,25,150,75,fill="blue")

root.mainloop()

#program to create arc

import tkinter

import tkinter.messagebox

top=tkinter.Tk()

c=tkinter.Canvas(top,bg="blue",height="250",width="300")

coord=10,50,240,210

arc=c.create_arc(coord,start=0,extent=150,fill="red")

c.pack()

top.mainloop()

#program for creating line

from tkinter import*

root=Tk()

w=Canvas(root,width=300,height=300,bg="red")

w.pack()

w.create_line(0,20,250,20,fill="yellow")

root.mainloop()

#program to create two lines

from tkinter import*

root=Tk()

l=Canvas(root,width=200,height=100,bg="red")

l.pack()

l.create_line(0,0,100,80,fill="blue")

l.create_line(0,0,80,100,fill="blue")

mainloop()

#program to create rectangle

from tkinter import*

master=Tk()

w=Canvas(master,width=200,height=100)

w.pack()

w.create_rectangle(50,25,150,75,fill="black")

mainloop()

#program to create two rectangles of colour yello and green

from tkinter import*

window=Tk()

s=Canvas(window,width=300,height=300)

s.pack()

s.create_rectangle(50,20,150,150,fill="#476042")

s.create_rectangle(70,50,200,230,fill="yellow")

#create a main window

fromtkinter import *

root=Tk()

root.mainloop()

#display variable using text variable option 

fromtkinter import *

root=Tk()

var=StringVar()

var.set("LONE_WOLFS")

l=Label(root,textvariable=var)

l.pack()

#display label and option 

fromtkinter import *

root=Tk()

L1=Label(root, text="Email")

L1.pack()

L2=Label(root, text="Password")

L2.pack()

b1=Button(root,text="Login")

b1.pack()

b2=Button(root,text="SignUp")

b2.pack()

root.mainloop()

#display label, entry box and button

fromtkinter import *

root=Tk()

L1=Label(root, text="Email")

L1.pack()

e1=Entry(root, bd=5)

e1.pack()

L2=Label(root, text="Password")

L2.pack()

e2=Entry(root, bd=5)

e2.pack()

b1=Button(root,text="Login")

b1.pack()

b2=Button(root,text="Cancel")

b2.pack()

root.mainloop()

#loading application

Using Pack() method

fromtkinter import *

root=Tk()

L=Label(root, text="FACEBOOK LOGIN", font=("ALGERIAN", 20), fg="BLUE")

L.pack()

L1=Label(root, text="Email")

L1.pack()

e1=Entry(root, bd=5)

e1.pack()

L2=Label(root, text="Password")

L2.pack()

e2=Entry(root, bd=5)

e2.pack()

b1=Button(root,text="Login")

b1.pack()

b2=Button(root,text="Cancel")

b2.pack()

root.mainloop()

#using grid method

fromtkinter import *

root=Tk()

L=Label(root, text="FACEBOOK LOGIN", font=("ALGERIAN", 20), fg="BLUE")

L.grid(column=1)

L1=Label(root, text="Email")

L1.grid(row=1)

L2=Label(root, text="Password")

L2.grid(row=2)

e1=Entry(root, bd=5)

e1.grid(row=1, column=1)

e2=Entry(root, bd=5)

e2.grid(row=2, column=1)

b1=Button(root,text="Login", fg="white", bg="GREEN")

b1.grid(column=1)

b2=Button(root,text="Cancel",fg="white", bg="RED")

b2.grid(column=1)

root.mainloop()

#textbox

fromtkinter import *

root = Tk()

T = Text(root, height=3, width=30)

T.pack()

T.insert(END, "Hi Friend\nWe are the Friends FOREVER\nThe Lone Wolfs.")

mainloop()

#entry box

fromtkinter import *

top = Tk()

L1 = Label(top, text="User Name")

L1.pack( side = LEFT)

E1 = Entry(top, bd =5)

E1.pack(side = RIGHT)

top.mainloop()

#frame

fromtkinter import*

root=Tk()

frame=Frame(root)

frame.pack()

bottomframe=Frame(root)

bottomframe.pack(side=BOTTOM)

red=Button(frame,text="red",fg="red")

red.pack(side=LEFT)

green=Button(frame,text="Green",fg="green")

green.pack(side=LEFT)

blue=Button(frame,text="Blue",fg="blue")

blue.pack(side=LEFT)

black=Button(bottomframe,text="Black",fg="black")

black.pack(side=LEFT)

root.mainloop()

#loading application using messagebox

fromtkinter import *

fromtkinter import messagebox

root=Tk()

def login():

username=e1.get()

password=e2.get()

if username="sandyjais" and password="Sudhir":

messagebox.showinfo("login","You Have Logged In Successfully.")

else:

messagebox.showinfo("login","Login Failed.")

def cancel():

root.destroy()

Label(root, text="FACEBOOK LOGIN", font=("ALGERIAN", 20), fg="BLUE").grid(column=1)

Label(root, text="username").grid(row=1)

e1=Entry(root, bd=5)

e1.grid(row=1, column=1)

Label(root, text="Password").grid(row=2)

e2=Entry(root, bd=5)

e2.grid(row=2, column=1)

b1=Button(root,text="Login", command=login)

b1.grid(row=3,column=1)

b2=Button(root,text="Cancel",command=cancel)

b2.grid(row=4,,column=1)

root.mainloop()

#checkbotton

fromtkinter import *

top = Tk()

CheckVar1 = IntVar()

CheckVar2 = IntVar()

C=Label(top,text="Select Your Favourite Programming Language.",fg="RED")

C.pack()

C1=Checkbutton(top,text="Python",variable=CheckVar1,onvalue=1,offvalue=0,height=5,

width=20)

C2=Checkbutton(top,text="Java",variable=CheckVar2,onvalue=1,offvalue=0,height=5, width=20)

C1.pack()

C2.pack()

top.mainloop()

#radiobutton

fromtkinter import *

defsel():

selection="You selected the option"+str(Var.get())

label.config(text=selection)

root=Tk()

Var=IntVar()

R1=Radiobutton(root,text="option1",variable=Var,value=1,command=sel)

R1.pack(anchor='c')

R2=Radiobutton(root,text="option2",variable=Var,value=2,command=sel)

R2.pack(anchor='c')

label=Label(root)

label.pack()

mainloop()

#messagebox

fromtkinter import *

fromtkinter import messagebox

root=Tk()

messagebox.showinfo("LOGIN","WELCOME SANDY_JAIS")

messagebox.showwarning("LOGIN","LOGIN FAILED.")

root.mainloop()

#listbox

fromtkinter import*

fromtkinter import messagebox

root=Tk()

l1=Listbox(root,relief=RAISED,selectmode="single")

l1.insert(1,"python")

l1.insert(2,"php")

l1.insert(3,"c")

l1.insert(4,"java")

l1.insert(5,"ruby")

l1.pack()

root.mainloop()

#messagebox

fromtkinter import*

root=Tk()

var=StringVar()

label=Message(root,textvariable=var,relief=RAISED)

label.pack()

var.set("welcome\nThe world of world of PROGRAMMING.")

root.mainloop()

#illsutrate the use of relief to widget

fromtkinter import*

root=Tk()

b1=Button(root,text="FLATE",relief=FLAT)

b2=Button(root,text="RAISED",relief=RAISED)

b3=Button(root,text="GROOVE",relief=GROOVE)

b4=Button(root,text="RIDGE",relief=RIDGE)

b5=Button(root,text="SUNKEN",relief=SUNKEN)

b1.pack()

b2.pack()

b3.pack()

b4.pack()

b5.pack()

root.mainloop()

#event handler using mousebutton

fromtkinter import *

root=Tk()

defcallback(event):

frame.focus_set()

print("clicked at",event.x,event.y)

frame=Frame(root,width=300,height=300,bg="RED")

frame.bind("<Button-1>", callback)

frame.pack()

mainloop()

#event handler using keyboard buttons 

fromtkinter import *

root=Tk()

def key(event):

print("Pressed",repr(event.char))

defcallback(event):

frame.focus_set()

print("clicked at",event.x,event.y)

frame=Frame(root,width=300,height=300,bg="RED")

frame.bind("<Key>",key)

frame.bind("<Button-1>", callback)

frame.pack()

mainloop()

#spinbox.

fromtkinter import *

master = Tk()

w = Spinbox(master, from_=0, to=10)

w.pack()

mainloop()

#spinbox color changing

fromtkinter import*

root=Tk()

t1=('green','red','blue','gray')

def colour():

str=w.get()

w.config(bg=str)

w=Spinbox(root,from_=0,to=10,value=t1,command=colour)

w.pack()

root.mainloop()

#create an application using different widget of tkinter

fromtkinter import *

root=Tk()

L=Label(root, text="FACEBOOK SIGNUP", font=("ALGERIAN", 20), fg="BLUE")

L.grid(row=1,column=3)

L1=Label(root, text="Full_Name")

L1.grid(row=2,column=1)

e1=Entry(root, bd=5)

e1.grid(row=2, column=2)

e2=Entry(root, bd=5)

e2.grid(row=2, column=3)

e3=Entry(root, bd=5)

e3.grid(row=2, column=4)

y=Label(root, text="LastName")

y.grid(row=3,column=2)

y1=Label(root, text="FirstName")

y1.grid(row=3,column=3)

y2=Label(root, text="MiddleName")

y2.grid(row=3,column=4)

L2=Label(root, text="Username")

L2.grid(row=4,column=1)

e4=Entry(root, bd=5)

e4.grid(row=4, column=2)

z1=Label(root, text=" ")

z1.grid(row=5,column=1)

L3=Label(root, text="Password")

L3.grid(row=6,column=1)

e5=Entry(root, bd=5)

e5.grid(row=6, column=2)

z2=Label(root, text=" ")

z2.grid(row=7,column=1)

L4=Label(root, text="Confirm Password")

L4.grid(row=8,column=1)

e6=Entry(root, bd=5)

e6.grid(row=8, column=2)

z3=Label(root, text=" ")

z3.grid(row=9,column=1)

L5=Label(root, text="Date of Birth")

L5.grid(row=10,column=1)

e7=Entry(root, bd=5)

e7.grid(row=10, column=2)

L6=Label(root, text="(dd/mm/yyyy)")

L6.grid(row=11,column=2)

z4=Label(root, text=" ")

z4.grid(row=9,column=1)

L5=Label(root, text="Gender")

L5.grid(row=12,column=1)

Var=IntVar()

R1=Radiobutton(root,text="Male",variable=Var,value=1)

R1.grid(row=12,column=2)

R2=Radiobutton(root,text="Female",variable=Var,value=2)

R2.grid(row=13,column=2)

R3=Radiobutton(root,text="Other",variable=Var,value=3)

R3.grid(row=14,column=2)

z5=Label(root, text=" ")

z5.grid(row=15,column=1)

L6=Label(root, text="Mobile_Number")

L6.grid(row=16,column=1)

e8=Entry(root, bd=5)

e8.grid(row=16, column=2)

z6=Label(root, text=" ")

z6.grid(row=17,column=1)

L7=Label(root, text="Location")

L7.grid(row=18,column=1)

t1=('India','UK','USA','Pakistan')

def colour():

str=w.get()

w.config(text=str)

w=Spinbox(root,from_=0,to=4,value=t1,command=colour)

w.grid(row=18,column=2)

z7=Label(root, text=" ")

z7.grid(row=19,column=1)

CheckVar1 = IntVar()

CheckVar2 = IntVar()

C1=Checkbutton(root,text="Accept terms and Conditions",variable=CheckVar1,onvalue=1,offvalue=0) 

C1.grid(row=20,column=2)

z8=Label(root, text=" ")

z8.grid(row=21,column=1)

b1=Button(root,text="SIGNUP", fg="white", bg="GREEN")

b1.grid(row=22,column=2)

b2=Button(root,text="CANCEL",fg="white", bg="RED")

b2.grid(row=22,column=3)

root.mainloop()

#create an oval

fromtkinter import *

root=Tk()

w=Canvas(root, width=300,height=300,bg="GRAY")

w.pack()

w.create_oval(60,60,250,250,fill="RED")

root.mainloop()

#create a face using canvas

fromtkinter import *

root=Tk()

f=Canvas(root, width=300,height=300)

f.create_oval(40,40,254,254,fill="red")

f.create_oval(90,80,113,101,fill="blue")

f.create_oval(193,80,212,103,fill="blue")

f.create_oval(87,199,199,209,fill="blue")

f.pack()

mainloop()

#program for mousehandler

from tkinter import *

root=Tk()

def callback(event):

    frame.focus_set()

    print("clicked at",event.x,event.y)

frame=Frame(root,width=300,height=300,bg="RED")

frame.bind("<Button-1>", callback)

frame.pack()

mainloop()

#program for keyboard handling

from tkinter import *

root=Tk()

def key(event):

    print("Pressed",repr(event.char))

def callback(event):

    frame.focus_set()

    print("clicked at",event.x,event.y)

frame=Frame(root,width=300,height=300,bg="RED")

frame.bind("<Key>",key)

frame.bind("<Button-1>", callback)

frame.pack()

mainloop()

#creating a table

import os

import sqlite3

conn1=sqlite3.c

onnect('sample_database')

csr=conn1.cursor()

str='create table employee1(E_id integer,name text)'

csr.execute(str)

conn1.close()

#inserting a values in table

import os

import sqlite3

conn1=sqlite3.connect('sample_database')

csr=conn1.cursor()

str1="insert into student values(1003,'sudhir')"

str2="insert into student values(1004,'Ashwin')"

str3="insert into student values(1005,'Deepak')"

str4="insert into student values(1006,'ramesh')"

try:

     csr.execute(str1)

     csr.execute(str2)

     csr.execute(str3)

     csr.execute(str4)

     conn1.commit()

except:

     conn1.rollback()

     conn1.close()

#Selecting from Student and printing Roll_no and Name column .

import os

import sqlite3

conn1=sqlite3.connect('sample_database')

csr=conn1.cursor()

sql="SELECT * FROM STUDENT"

try:

     csr.execute(sql)

     result=csr.fetchall()

     print("ROLL_NO   NAME   ")

     for row in result:

          rno=row[0]

          sname=row[1]

          print("%d      %s      "%(rno,sname))

except:

     print"Error:unable to fetch data"

conn1.close()

#Connect mysql.connector and give statement.

import mysql.connector

from mysql.connector import Error

try:

     conn=mysql.connector.connect(host='localhost',

                                  database='ritesh',

                                  user='root',

                                  password='')

     if conn.is_connected():

          print('connected to Mysql database')

     csr=conn.cursor()

     str="select * from Item"

     csr.execute(str)

     result=csr.fetchall()

     print("INO      INAME            PRICE          QUANTITY")

     for row in result:

          ino=row[0]

          iname=row[1]

          p=row[2]

          q=row[3]

          print(" %d      %s       %d             %d  "%(ino,iname,p,q))

except Error as e:

     print(e)

finally:

     conn.close()

#Sending mail using SMTP

import smtplib

# creates SMTP session

s = smtplib.SMTP('smtp.gmail.com', 587)

# start TLS for security

s.starttls()

# Authentication

s.login("sender_email_id", "sender_email_id_password") 

# message to be sent

message = "Message_you_need_to_send"

# sending the mail

s.sendmail("sender_email_id", "receiver_email_id", message)

# terminating the session

s.quit()

#Sending mail to multiple persons.

import smtplib 

# list of email_id to send the mail

li = ["xxxxx@gmail.com", "yyyyy@gmail.com"]

for i in range(len(li)):

    s = smtplib.SMTP('smtp.gmail.com', 587)

    s.starttls()

    s.login("sender_email_id", "sender_email_id_password")

    message = "Message_you_need_to_send"

    s.sendmail("sender_email_id", li[i], message)

    s.quit()