In task-level programming, using menu selection statements to input instructions is a common and user-friendly way.
This method allows users to perform different tasks or operations by selecting options in the menu.
The following is a simple example showing how to use Python language to implement menu-based instruction input.
python code
def main_menu():
print("Welcome to the system menu")
print("1. Display welcome message")
print("2. Calculate the sum of two numbers")
print("3. Exit")
while True:
try:
choice = int(input("Please enter your choice (1-3):"))
if choice == 1:
show_welcome_message()
elif choice == 2:
calculate_sum()
elif choice == 3:
print("Thank you for using, goodbye!")
break
else:
print("Invalid input, please reselect.")
except ValueError:
print("Please enter a valid number.")
def show_welcome_message():
print("Welcome to this system!")
def calculate_sum():
num1 = float(input("Please enter the first number:"))
num2 = float(input("Please enter the second number:"))
print(f"{num1} and {num2} is: {num1 + num2}")
if __name__ == "__main__":
main_menu()
In this example, the `main_menu()` function is responsible for displaying the main menu and processing user input. It first prints out the menu options and then enters an infinite loop, waiting for user input. After the user enters a number, the program checks whether the number corresponds to an option in the menu.
If it does, the corresponding function (such as `show_welcome_message()` or `calculate_sum()`) is executed. If the input is invalid (that is, not 1, 2, or 3), the program prompts the user to re-enter. If the user chooses to exit (that is, enters 3), the loop terminates and the program ends.
Note that the `try...except` statement is used here to handle the `ValueError` exception that may be raised by the user input, which usually occurs when the user enters something other than a number. This can improve the robustness of the program and the user experience.
This example shows the basic method of using menu selection statements to input instructions in task-level programming. You can expand and modify this framework as needed to adapt to more complex application scenarios.