Error & Exception Handling in Python

try:
    x = int("abc")
except ValueError:
    print("Wrong input")
except TypeError:
    print("Type issue")
except Exception as e:
    print("Other issue:", e)

try:
    f = open("file.txt", "r")
    data = f.read()
except FileNotFoundError:
    print("File not found.")
else:
    print("File read successfully.")
finally:
    print("This block will always execute.")

def check_age(age):
    if age < 18:
        raise ValueError("Age must be 18 or older!")
    return "Access granted."

try:
    print(check_age(20))  # Access granted.
    print(check_age(16))  # Raises ValueError
except ValueError as e:
 print(f"Error: {e}")

import tkinter as tk
from tkinter import messagebox

def calculate(operation):
    try:
        num1 = float(entry1.get())
        num2 = float(entry2.get())

        if operation == '+':
            result = num1 + num2
        elif operation == '-':
            result = num1 - num2
        elif operation == '*':
            result = num1 * num2
        elif operation == '/':
            result = num1 / num2
        else:
            result = "Invalid Operation"

        result_label.config(text="Result: " + str(result))

    except ValueError:
        messagebox.showerror("Input Error", "कृपया केवल संख्याएँ दर्ज करें।")
    except ZeroDivisionError:
        messagebox.showerror("Math Error", "0 से भाग नहीं कर सकते।")
    except Exception as e:
        messagebox.showerror("Unknown Error", str(e))

# GUI window बनाना
window = tk.Tk()
window.title("Simple Calculator")
window.geometry("300x250")

# Entry fields
tk.Label(window, text="पहली संख्या:").pack()
entry1 = tk.Entry(window)
entry1.pack()

tk.Label(window, text="दूसरी संख्या:").pack()
entry2 = tk.Entry(window)
entry2.pack()

# Operation buttons
tk.Label(window, text="ऑपरेशन चुनें:").pack(pady=5)
tk.Button(window, text="+", width=5, command=lambda: calculate('+')).pack()
tk.Button(window, text="-", width=5, command=lambda: calculate('-')).pack()
tk.Button(window, text="*", width=5, command=lambda: calculate('*')).pack()
tk.Button(window, text="/", width=5, command=lambda: calculate('/')).pack()

# Result label
result_label = tk.Label(window, text="Result: ")
result_label.pack(pady=10)

# Start GUI loop
window.mainloop()

class InvalidAgeError(Exception):
    """Custom exception for invalid age."""
    def __init__(self, message="Age must be 18 or older!"):
        self.message = message
        return super().__init__(self.message)

def verify_age(age):
    if age < 18:
        raise InvalidAgeError()  # Raise your custom exception
    return "Welcome!"



try:
    print(verify_age(16))
except InvalidAgeError as e:
    print(f"Error: {e}")