相关疑难解决方法(0)

如何使用JavaScript在switch case语句中使用范围？因此,我不想为每种可能性编写代码,而是将它们分组到范围中,例如:

switch(myInterval){
   case 0-2:
      //doStuffWithFirstRange();
      break;

   case 3-6:
      //doStuffWithSecondRange();
      break;

   case 6-7:
      //doStuffWithThirdRange();
      break;

   default:
      //doStuffWithAllOthers();
}

是否有可能重构并完全避免使用if else else语句以获得更好的可读性.例如 :

 function canIWatch(age) {
if (age < 6 && age > 0) return "You are not allowed to watch Deadpool after 6:00pm.";
else if (age >=6 && age < 17) return "You must be accompanied by a guardian who is 21 or older.";
else if (age >=17 && age < 25) return "You are allowed to watch Deadpool, right after you show some ID.";
else if (age >= 25 && age < 50 ) return "Yay! You …

如何使这些javascript语句看起来更具可读性.函数库ramda.js可以用来使这段代码看起来更好吗？

var getTextSpace =  function(len)
    {
            var tlength;
            if (len >= 1 && len <= 4) {
                tlength = 10;
            } else if (len === 5) {
                tlength = 14;
            } else if (len === 6) {
                tlength = 16;
            } else if (len === 7) {
                tlength = 18;
            } else if (len >= 8 && len <= 10) {
                tlength = 20;
            } else if (len === 11) {
                tlength = 22;
            } else if (len === 12) …

据我所知,代码工作正常,但是当添加或编辑更多信息时,if else语句开始表现奇怪.它正确读取百分比值,但它没有返回正确的字母字符串.

var total = function (){
    var earned = 0;

     for(i = 0; i < Assignments.length; i++){
         earned += parseInt(Assignments[i].earned);
     }
     var possible = 0;

     for(i = 0; i < Assignments.length; i++){
         possible += parseInt(Assignments[i].possible);
     }
     var percent = (Math.floor((earned/possible) * 100));

     console.log(percent);

  //grade letter

      if (percent >= 90){
         grade.innerHTML = '';
         grade.innerHTML = 'A ' + percent + '%';
      } else if (percent <= 89 && 80 >= percent){
         grade.innerHTML = '';
         grade.innerHTML = 'B ' + percent …