Strings aur String Methods

String bas text hota hai, aur Python ise characters ki ek sequence ki tarah treat karta hai — iska matlab hai ki aap isme index kar sakte ho aur slice kar sakte ho, bilkul list ki tarah.

greeting = "Hello, World!"
print(greeting[0])
print(greeting[7:12])
print(greeting.upper())
print(greeting.lower())
print(len(greeting))

H
World
HELLO, WORLD!
hello, world!
13

• greeting[0] index 0 par jo character hai woh deta hai — Python 0 se index karta hai, 1 se nahi
• greeting[7:12] ek slice hai — index 7 se lekar (including nahi) index 12 tak ke characters
• .upper() aur .lower() ek naya string return karte hain, original ko change nahi karte
• len() strings par bhi waise hi kaam karta hai jaise lists par karta hai

f-strings — text banane ka modern tarika

Aapko baar baar variables ko fixed text ke saath combine karna padega. f-strings (string ke aage f lagao) aapko curly braces use karke variable ko seedhe string mein daalne dete hain, + se pieces ko clumsily jodne ke bajaye.

name = "Abhimanyu"
age = 25
print(f"My name is {name} and I am {age} years old.")

My name is Abhimanyu and I am 25 years old.

Splitting aur replacing

.split() ek string ko list mein tod deta hai, jahan bhi aapne diya hua separator milta hai. .replace() ek substring ko doosre se replace kar deta hai, jahan bhi woh milta hai.

sentence = "Python is fun"
words = sentence.split(" ")
print(words)
print(sentence.replace("fun", "powerful"))

['Python', 'is', 'fun']
Python is powerful

Aage: lists — Python mein values ki ordered collection store karne ka core tarika.