PHP实现按分钟计算停车时长收费功能的技术咨询

Hey there! Let's get your parking fee calculator working reliably for any duration, not just the first two hours. First, let's break down the gaps in your current code:

• It hardcodes the parking time as 10 minutes, so it can't handle different input values.
• It only accounts for durations under 2 hours—anything over 120 minutes will throw an error because $time_parked isn't defined in that case.
• The return statements inside your if/elseif blocks mean the final echo line will never run (the function exits before reaching it).

Here's the Improved Solution #

Based on your requirements:

• $50 for 1 hour (or less)
• $100 for the 1–2 hour interval
• $200 for 2–3 hours, and so on (each additional hour interval doubles the fee)

We can create a reusable, dynamic function that handles all scenarios:

function calculateParkingFee(int $minutes): float {
    $baseRate = 50.0;
    
    // Ensure we use at least 1 interval (even for 0 minutes, per your "1 hour (含)以内" rule)
    $hourIntervals = max(1, ceil($minutes / 60));
    
    // Calculate fee: each interval after the first doubles the base rate
    $totalFee = $baseRate * (2 ** ($hourIntervals - 1));

    echo "Amount to pay: $" . number_format($totalFee, 2) . "\n";
    return $totalFee;
}

// Test with different parking durations
calculateParkingFee(10);   // Output: Amount to pay: $50.00
calculateParkingFee(60);   // Output: Amount to pay: $50.00
calculateParkingFee(61);   // Output: Amount to pay: $100.00
calculateParkingFee(120);  // Output: Amount to pay: $100.00
calculateParkingFee(121);  // Output: Amount to pay: $200.00
calculateParkingFee(240);  // Output: Amount to pay: $400.00
calculateParkingFee(0);    // Output: Amount to pay: $50.00

Key Details Explained: #

• Parameterized Input: The function accepts $minutes as an argument, so you can pass any parking duration instead of hardcoding it.
• Interval Calculation: ceil($minutes / 60) rounds up minutes to the next full hour interval (e.g., 61 minutes becomes 2 intervals for the 1–2 hour window). Using max(1, ...) ensures even 0 minutes uses the 1-hour interval rule.
• Doubling Logic: 2 ** ($hourIntervals - 1) handles the fee doubling: for 1 interval, it’s 2^0 = 1 ($50), for 2 intervals it’s 2^1 = 2 ($100), and so on.
• Clean Currency Output: number_format() formats the fee to two decimal places, matching standard currency display.

内容的提问来源于stack exchange，提问作者Leandro Matilla