javascript - 如何将数组拆分为奇数数组和偶数数组

Question

我在将数组拆分为单独的奇数数组和偶数数组时遇到问题。我所做的是:

componentDidMount() {
 axios.get( `${this.props.cmsUrl}types/genres`)
 .then(response => { if ( response.data !== undefined ) {

  let even = [];
  let odd = [];
  let allData = ["a", "b", "c", "d", "e", "f", "g", "h", ];

  for (var i = 0; i < allData.length; ++i) {
    if ( ( allData[i] % 2 ) === 0) { 
      even.push(allData[i]);
    } 
    else { 
      odd.push(allData[i]); 
    }
  };
  console.log("allData : ",allData);
  console.log("even : ",even);
  console.log("even : ",odd);
 }}
)
}

我真正期待的是

allData = [a, b, c, d]
odd = [a , c]
even = [b, d]

但真正发生的事情是

allData = even 
odd = empty array

这是我的问题吗 => ( allData[i] % 2 ) === 1

console.log 是:

  allData :  (8) ["a", "b", "c", "d", "e", "f", "g", "h"]0: "a"1: "b"2: "c"3: 
  "d"4: "e"5: "f"6: "g"7: "h"length: 8__proto__: Array(0)
    details.js:56 even :  []length: 0__proto__: Array(0)
    details.js:57 odd :  (8) ["a", "b", "c", "d", "e", "f", "g", "h"]0: 
   "a"1: "b"2: "c"3: "d"4: "e"5: "f"6: "g"7: "h"length: 8__proto__: Array(0)

谢谢

Answer 1

您必须使用 charCodeAt 方法，因为 allData 是字符串数组而不是数字数组。

这是您问题的解决方案:

if ( ( allData[i].charCodeAt(0) % 2 ) === 0) { your code }

==================

正如Thomas Scheffer提到的那样，您似乎想根据字符索引而不是其值进行排序。

所以如果你想根据索引排序你必须写:

if ( ( i % 2 ) === 0) { your code }

它的转换如下:

allData = ["b","f","z","w"] => { odd=["f","w"], even=["b","z"]  }

但是如果你想根据字符值排序，你必须写:

if ( ( allData[i].charCodeAt(0) % 2 ) === 0) { your code }

它的转换如下:

allData = ["b","f","z","w"] => { odd=["w"] , even=["b","f","z"] }