javascript - 如何使用 javascript 识别数组中的自定义值？

Question

我做了一个调查，受访者有一个选择题，比方说:“你最喜欢的水果是什么？”，他们可以从列表中随意选择，也可以引入自定义值以防他们想要添加未列出的水果。该列表有以下选项:apple、pear、banana、strawberry 和“custom”。

我需要制作一个包含信息的图表来计算有多少人选择了每种水果。但我会将所有自定义值添加到一个名为“自定义”的值中。假设我最终得到了这样一个数组:

[
  {
    "Person": "Person1",
    "Fruits": [ "apple", "banana", "peach" ]
  },
  {
    "Person": "Person2",
    "Fruits": [ "apple", "pear", "strawberry", "coconut" ]
  },
  {
    "Person": "Person3",
    "Fruits": [ "pear", "strawberry" ]
  },
  {
    "Person": "Person4",
    "Fruits": [ "strawberry", "orange" ]
  }
]

为了计算已经列出的水果，我开始使用 includes()，但 IE 不支持它。所以我正在使用我找到的代码 Alternative of .includes() in Internet Explorer .

我的代码:
我为数组中的每个元素创建了一个循环，如果它包含某个单词，它就会存储在对应的数组中:

//I am calling the info with AngularJS don't know if is important to know that
//Declare empty arrays for each fruit
var dataResults = $scope.items, //<---- this is the array with the info, the one I showed before..
    apple = [],
    pear = [],
    banana = [],
    strawberry = [],
    custom = [];

//function to read if an array includes a certain value
function includes(container, value) {
    var returnValue = false;
    var pos = container.indexOf(value);
    if (pos >= 0) {
        returnValue = true;
    }
    return returnValue;
}

//Loop the survey results
for(var i=0; i<dataResults.length; i++) {
    var currentItem = dataResults[i];
    //I push the name of the person if he/she chose apple
    if(includes(currentItem.Fruits, "apple")){
        apple.push(currentItem.Person);
    }
    //I push the name of the person if he/she chose pear
    if(includes(currentItem.Fruits, "pear")){
        pear.push(currentItem.Person);
    }
    //I push the name of the person if he/she chose banana
    if(includes(currentItem.Fruits, "banana")){
        banana.push(currentItem.Person);
    }
    //I push the name of the person if he/she chose strawberry
    if(includes(currentItem.Fruits, "strawberry")){
        strawberry.push(currentItem.Person);
    }
};
//now I wanna see the results in the console for each array
console.log("apple: " + apple.length);
console.log("pear: " + pear.length);
console.log("banana: " + banana.length);
console.log("strawberry: " + strawberry.length);

但现在我不知道有多少人输入了自定义值。他们写什么并不重要(因为可能有数百个不同的值)，但我需要将它们全部存储为“自定义”。
如何计算未出现在列表中的值？
请帮忙。

Answer 1

看起来是 switch 的不错选择给我的声明。

您还可以删除使用 includes() 的需要。

例如:

//Loop the survey results
var currentItem, f, max;
for(var i=0; i<dataResults.length; i++) {
    currentItem = dataResults[i];
    max = currentItem.Fruits.length;
    for(f=0;f<max;f++) {
        switch(currentItem.Fruits[f]) {
            case "apple" :
                apple.push(currentItem.Person);
                break;
            case "pear" :
                pear.push(currentItem.Person);
                break;
            case "banana" :
                banana.push(currentItem.Person);
                break;
            case "strawberry" :
                strawberry.push(currentItem.Person);
                break;
            default :
                custom.push(currentItem.Person);
        }
    }
}