Javascript代码

        // Build 12-digit base barcode (without checksum)
        const base = `238880103521`;
        
        // Calculate EAN13 checksum
        const checksum = base.split('').reduce((sum, digit, index) => sum + parseInt(digit) * (index % 2 === 0 ? 1 : 3), 0);
        const checksumDigit = (10 - (checksum % 10)) % 10;
        
        // Complete 13-digit barcode : 2388801035215
        const barcode = `${base}${checksumDigit}`;