javascript JS - 日期功能（WIP 20190115）

Posted 2021-05-03

(function() {
  let dateText = document.getElementById("today-tomorrow");
  let todayDate =  new Date(); // Store date object for today
  let tomorrowDate = new Date();
  tomorrowDate.setDate(todayDate.getDate()+1); //Store date object for tomorrow

  //Store numerical hours, day & month values for today
  let todayMonth = todayDate.getMonth() + 1;
  let todayDay = todayDate.getDate();

  //Store numberical day & month values for tomorrow
  let tomorrowMonth = tomorrowDate.getMonth() + 1;
  let tomorrowDay = tomorrowDate.getDate();

  //If it's before 1pm, it ships within 24 hours, otherwise it ships tomorrow.
  if (todayDate.getHours() < 13) {
      //insertText( dateText, "today, " + getMonthName(todayMonth-1) + " " + getDateText(todayDay) );
      insertText( dateText, "{{lang 'single_product_page.hours'}}");
  //} else if ( (!(todayDate.getHours() < 13)) && ( todayDay.getDay > 4 ) ) {
  //    //insertText( dateText, "tomorrow, " + getMonthName(tomorrowMonth) + " " + getDateText(tomorrowDay) );
  //    insertText( dateText, "on Monday.");
  } else {
      insertText( dateText, "{{lang 'single_product_page.tomorrow'}}");
  }

  //Inserts text into an element via the innerHTML property.
  function insertText (element, text) {
      element.innerHTML = text;
  }

  //Takes in a numerical day of the week and returns the text version.
  function dayOfWeekText (dayNumber) {
      switch (dayNumber) {
          case 0:
              return "Sunday";
          case 1:
              return "Monday";
          case 2:
              return "Tuesday";
          case 3:
              return "Wednesday";
          case 4:
              return "Thursday";
          case 5:
              return "Friday";
          case 6:
              return "Saturday";
          default:
              return "Wrong Date Number";
      }
  }

  //Takes in a numerical month and returns the name of the month.
  function getMonthName (monthNumber) {
      let months = ["{{lang 'general.months.jan'}}", 
                    "{{lang 'general.months.feb'}}",
                    "{{lang 'general.months.mar'}}",
                    "{{lang 'general.months.apr'}}",
                    "{{lang 'general.months.may'}}",
                    "{{lang 'general.months.jun'}}",
                    "{{lang 'general.months.jul'}}",
                    "{{lang 'general.months.aug'}}",
                    "{{lang 'general.months.sep'}}",
                    "{{lang 'general.months.oct'}}",
                    "{{lang 'general.months.nov'}}",
                    "{{lang 'general.months.deck'}}"];
      return months[monthNumber];
  }

  //Takes in a numerical day of the month and returns the text version with suffix.
  //example ==> passing a 1 would return '1st', passing a 15 would return '15th'.
  function getDateText (dateNumber) {
      if (dateNumber) {
          return dateNumber + dateSuffix(lastDigit(dateNumber));
      }
  }

  //Returns last digit of a given number, in the case of a single digit number,
  //returns that single digit.
  function lastDigit (number) {
      if (number < 10) {
          return number;
      } else {
          return number % 10;
      }
  }

  //Takes in a single digit and returns a string containing the appropriate suffix such as 'st', 'nd', 'rd', etc.
  //example: 1 returns 'st', 2 returns 'nd'
  function dateSuffix (lastDigit) {
      switch (lastDigit) {
          case 1:
              return "st";
          case 2:
              return "nd";
          case 3:
              return "rd";
          default:
              return "th";
      }
  }
})();