为什么此功能不能删除元音？

Question

我创建了一个函数，该函数使用字符串将字符串转换为数组，然后将每个字符串字符与数组中的每个元音进行比较，如果匹配，则删除该字符串字符。在更长的单词上似乎无法正常工作。例如，使用“ tom”将删除o，但使用“ johnson”将仅删除第一个o，然后在末尾也删除n。我没有看到这个问题。

function removeVolwels(string){

  let strAr= function(string){
     //converts to to lower case and turns string into an array
      let s= string.toLowerCase();
      let strAr= s.split("");
      return strAr;
  }(string);
   //stores vowels
  let vowels=["a","e","o","i","u","y"];

  //loops through each character
  for(let i=0; i < string.length -1; i++){
      console.log("i index " + i);
  //compares each  character in the string to a every vowel until it matches one
      for(let j=0; j < vowels.length; j++){
          console.log("j index " + j + " and " +vowels[j]);
         if(string[i] === vowels[j]){
              console.log(string[i].toString() + " === "+vowels[j]);
             console.log("removed " + string[i]);
            //removes vowel if letter matches one
             strAr.splice(i,1);
             console.log(strAr)
         } 
      }
  }
  
  return strAr.join("");
}

console.log('tom => ' + removeVolwels('tom'));
console.log('johnson => ' + removeVolwels('johnson'));

Answer 1

问题是您打电话给strAr.splice(i,1);。

因此，您有单词“ johnson”，并且在删除第一个“ o”之后得到了“ jhnson”，但是当前字符串的长度是6而不是开头的7！

当您到达下一个“ o”时-的i值为5（对于“ johnson”字符串正确，但对“ jhnson”不是正确的）。

另外，循环中还有另一个错误-您有condition i < string.length -1。这意味着您将永远无法达到最后一个角色。应该是i < string.length。

因此，如果您想重用解决方案，则可以编写以下内容：

function removeVolwels(string){

  let strAr= function(string){
     //converts to to lower case and turns string into an array
      let s= string.toLowerCase();
      let strAr= s.split("");
      return strAr;
  }(string);
   //stores vowels
  let vowels=["a","e","o","i","u","y"];
  let returnVal = [];
  //loops through each character
  for(let i=0; i < string.length; i++){
      console.log("i index " + i);
      // simple flag to match if letter should be added to return array
      let shouldBeAdded = true;
      //compares each  character in the string to a every vowel until it matches one
      for(let j=0; j < vowels.length; j++){
          console.log("j index " + j + " and " +vowels[j]);
          if(string[i] === vowels[j]){
              // when it is some of the vowels it should not be added, so we change the flag, and break 'vowel loop'
              shouldBeAdded = false;
              break;
          } 
      }
      // if flag is true then add letter to result array
      if(shouldBeAdded === true) {
          returnVal.push(string[i])
      }
  }
  
  return returnVal.join("");
}

console.log('tom => ' + removeVolwels('tom'));
console.log('johnson => ' + removeVolwels('johnson'));