如何在 JavaScript 中以递增顺序在对象中添加属性

您可以浏览并删除作为键存在的字符，然后返回并添加剩余的内容

https://jsfiddle.net/stevenkaspar/krzz9zmf/8/

var alpha_num_array = [
'1','2','3','4',
'5','6','7','8','9',
'0',
'a','b','c','d','e',
'f','g','h','i','j',
'k','l','m','n','o',
'p','q','r','s','t',
'u','v','w','x','y',
'z'];
key_arr.map(function(k){
  if(!k.shortkeys) return;
  var key = k.shortkeys.split('+')[1];
  var key_index = alpha_num_array.indexOf(key);
  alpha_num_array.splice(key_index, 1);
})
key_arr = key_arr.map(function(k){
  if(k.shortkeys) return k;
  k.shortkeys = 'alt+'+alpha_num_array[0];
  alpha_num_array.shift();
  return k;
})
console.log(key_arr);

var arr=[
  {name:"abc",shortkeys:"alt+m"},
  {name:"c_1"},
  {name:"abc",shortkeys:"alt+t"},
  {name:"abc",shortkeys:"alt+c"},
  {name:"wes_2"},
  {name:"ncv_3"},
  {name:"sghb_4"},
  {name:"ijo_5"},
  {name:"nhio_6"},
  {name:"jion_7"},
  {name:"chudoi_8"},
  {name:"bdmki_9"},
  {name:"dssd_0"},
  {name:"sdfs_a"},
  {name:"abc",shortkeys:"alt+4"},
  {name:"abc",shortkeys:"alt+e"},
  {name:"sghb_b"},
  {name:"ijo_d"},
  {name:"gsha_e"},
  {name:"asdas_f"},
  {name:"bbb_g"},
  {name:"mko_h"},
  {name:"kioh_i"},
  {name:"qwee_j"},
  {name:"qwee_k"},
  {name:"qwee_l"},
  {name:"qwee_n"},
];
//possible shortkeys reversed so we can pop them off
var keys = [
  '1','2','3','4','5','6','7','8','9','0'
  ,'a','b','c','d','e','f','g','h','i','j'
  ,'k','l','m','n','o','p','q','r','s','t'
  ,'u','v','w','x','y','z'].reverse();
//elements without a shortkeys
var tagsWithoutShortcuts = arr.filter(function(element){ return typeof element.shortkeys === 'undefined'; });
console.log(keys);
console.log(tagsWithoutShortcuts);
tagsWithoutShortcuts.forEach(function(tag){
  var key = keys.pop();
  //while key is already used, get another
  while (arr.filter(function(element){ return element.shortkeys === 'alt+'+ key; }).length) key = keys.pop();
  //put the shortkeys on the tag
  tag.shortkeys = 'alt+'+ key;
});
console.log(arr);

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>

您现有尝试的错误(除了没有得到您想要的字母(是......

• 您在声明var obj后myObj使用了错误的变量名
• 你有if (!'shortkeys' in myObj){而不是if (!('shortkeys' in myObj)){
• 在分配现有shortkeys之前，您未能查找现有

在此代码中，我...

• 添加了一个跟踪所有已使用的快捷键(包括当前存在的快捷键(的对象
• 添加了一个循环，该循环会不断寻找唯一的快捷键，直到找到一个
• 添加了用于获取a-z字符的alpha变量
• 在主for循环中添加了一个OUTER标签，以便我们可以在超过字母z时中断循环。标签是必需的，因为我们正在打破内部do-while循环。

var arr=[
  {name:"abc",shortkeys:"alt+m"}, {name:"c_1"}, {name:"abc",shortkeys:"alt+t"}, {name:"abc",shortkeys:"alt+c"},
  {name:"wes_2"}, {name:"ncv_3"}, {name:"sghb_4"}, {name:"ijo_5"}, {name:"nhio_6"}, {name:"jion_7"},
  {name:"chudoi_8"}, {name:"bdmki_9"}, {name:"dssd_0"}, {name:"sdfs_a"}, {name:"abc",shortkeys:"alt+y"},
  {name:"abc",shortkeys:"alt+e"}, {name:"sghb_b"}, {name:"ijo_d"}, {name:"gsha_e"}, {name:"asdas_f"},
  {name:"bbb_g"}, {name:"mko_h"}, {name:"kioh_i"}, {name:"qwee_j"}, {name:"qwee_k"}, {name:"qwee_l"}, {name:"qwee_n"}
]
var j = 1;
var alpha = 'a'.charCodeAt(0); // Number for the 'a-z' chars
var z = 'z'.charCodeAt(0); // Number for the 'z' character
var shorts = {}; // Holds all shortkeys to avoid duplicates
var short = "";
// First gather all the existing shortkeys
for (var i = 0; i < arr.length; i++) {
  if (arr[i].shortkeys) {
    shorts[arr[i].shortkeys] = arr[i].shortkeys
  }
}
OUTER:
for (var i = 0; i < arr.length; i++) {
  var myObj = arr[i];
  
  if (!('shortkeys' in myObj)) {
    // We want to make sure that our "short" is not yet used.
    do {
      if (j < 10) {
        short = 'alt+' + j
        j++;
        
      } else if (j == 10) {
        short = 'alt+0'
        j++;
        
      } else if (alpha <= z) {
        short = 'alt+' + String.fromCharCode(alpha);
        alpha++;
        
      } else {
      	break OUTER; // We've moved beyond 'z', so just quit.
      }
    } while(short in shorts)
    
    // Track the new shortkey, and assign it
    shorts[short] = short
    myObj.shortkeys = short
  }
}
document.querySelector("pre").textContent = JSON.stringify(arr, null, 4)

<pre></pre>

注意。。。

• 你的预期输出有一个错误;它有两次alt+e。
• 无需手动创建值数组，因为字符映射到数字