将DD/MM/YYYY格式转换为YYYY-MM-DD

function formatDate(dateString) {
  var parts = dateString.split('/');
  var formattedDate = parts[2] + '-' + parts[1] + '-' + parts[0];
  return formattedDate;
}

var inputDate = '31/12/2022';
var formattedDate = formatDate(inputDate);
console.log(formattedDate); // 输出：2022-12-31

from datetime import datetime

def format_date(date_string):
    date_object = datetime.strptime(date_string, '%d/%m/%Y')
    formatted_date = date_object.strftime('%Y-%m-%d')
    return formatted_date

input_date = '31/12/2022'
formatted_date = format_date(input_date)
print(formatted_date)  # 输出：2022-12-31