JSFiddle對象排序算法崩潰

我很抱歉，如果它是一個愚蠢的問題，我正在爲一個JS考試學習，我採取了一個隨機的分配任務，我在JSFiddle中按年排序來自URL的JSON數據。代碼放在爲：JSFiddle對象排序算法崩潰

https://jsfiddle.net/gs6eey97/ (i apologize for all the comments).

第一個問題是，控制檯將返回排序列表，但每種分選的元素在排序列表中出現兩次（Console result）。我想過加入一個if語句剛剛整理之前的數據被放在

minYear.push(minYearPom); 
minSort.push(propPom);

以下內容：：

if (propPom != minSort[minSort.length - 1]) { 
     minYear.push(minYearPom); 
     minSort.push(propPom); 
     }

和鉻停止respo陣列通過改變以下過濾重複nding，我已經試過刪除

minYear.push(minYearPom);

，因爲我意識到我並不真的需要它，而Chrome停止響應，我添加了簡單的console.log看到某些變量的值來揣摩出了什麼問題是，Chrome停止響應。朋友似乎無法找到代碼的問題，所以如果任何人都可以找到問題，我會非常感激。

來源

2017-04-18 PingvinSero

當你得到對象的對象，

{ 
    movies: { 
     tt0111161: { 
      Title: "The Shawshank Redemption", 
      Year: "1994", 
      Runtime: "142", 
      Director: "Frank Darabont", 
      Actors: [ 
       "Tim Robbins", 
       "Morgan Freeman", 
       "Bob Gunton", 
       "William Sadler" 
      ], 
      Language: [ 
       "English" 
      ], 
      imdbRating: "9.3", 
      imdbVotes: "138" 
     }, 
     // ... 
    } 
}

你需要採取的鑰匙，就像tt0111161等，並應用鍵陣列上的排序：

var data = { movies: { tt0111161: { Title: "The Shawshank Redemption", Year: "1994", Runtime: "142", Director: "Frank Darabont", Actors: ["Tim Robbins", "Morgan Freeman", "Bob Gunton", "William Sadler"], Language: ["English"], imdbRating: "9.3", imdbVotes: "138" }, tt0068646: { Title: "The Godfather", Year: "1972", Runtime: "175", Director: "Francis Ford Coppola", Actors: ["Marlon Brando", "Al Pacino", "James Caan", "Richard S. Castellano"], Language: ["English", "Italian", "Latin"], imdbRating: "9.2", imdbVotes: "96" } } }, 
 
    keys = Object.keys(data.movies); 
 

 
keys.sort(function (a, b) { 
 
    return data.movies[a].Year - data.movies[b].Year; 
 
}); 
 

 
console.log(keys);

.as-console-wrapper { max-height: 100% !important; top: 0; }

來源

2017-04-18 16:51:14

我們ü本身Object.prototype.values()獲取電影作爲對象的數組：

的Object.values()方法返回給定的對象自身枚舉屬性值的數組，以相同的順序作爲由 for...in loop提供（不同之處在於一個for-in循環枚舉了原型鏈中的屬性）。

let movies = Object.values(data.movies); 

/* 
movies = [ 
    { "Title": "The Shawshank Redemption", ... }, 
    { "Title": "The Godfather", ... }, 
    ... 
]; 
*/

currentYear用於計算膜的年齡

我們然後用Array.prototype.sort()電影排序：

的sort()方法到位並返回排序的數組元素數組。排序不一定穩定。默認排序順序根據字符串Unicode代碼點。

movies.sort((a, b) => a.Year - b.Year);

對於我們使用Array.prototype.reduce()

的reduce()方法的膜的平均年齡應用於對一個儲液器的功能和陣列中的每個元件（從左至右），以減少它以單一的值。

let avg = movies.reduce((result, currentMovie) => result + (currentYear - currentMovie.Year), 0)/movies.length;

在片斷也可用於但用於排序/平均部分不相關：

Arrow function (... => ...)

箭頭函數表達式具有比功能表達較短的語法和不不綁定自己的this，arguments，super，或者new.target。這些函數表達式最適合非方法函數，並且它們不能用作構造函數。

Template literals (`...${...}...`)

模板文字是字符串常量，允許嵌入的表達式。您可以使用多行字符串和字符串插值功能與他們。在之前版本的ES2015規範中，它們被稱爲「模板字符串」。

let data = { "movies":{ "tt0111161":{ "Title":"The Shawshank Redemption", "Year":"1994", "Runtime":"142", "Director":"Frank Darabont", "Actors":["Tim Robbins", "Morgan Freeman", "Bob Gunton", "William Sadler"], "Language":["English"], "imdbRating":"9.3", "imdbVotes":"138" }, "tt0068646":{ "Title":"The Godfather", "Year":"1972", "Runtime":"175", "Director":"Francis Ford Coppola", "Actors":["Marlon Brando", "Al Pacino", "James Caan", "Richard S. Castellano"], "Language":["English", "Italian", "Latin"], "imdbRating":"9.2", "imdbVotes":"96" }, "tt0071562":{ "Title":"The Godfather: Part II", "Year":"1974", "Runtime":"200", "Director":"Francis Ford Coppola", "Actors":["Al Pacino", "Robert Duvall", "Diane Keaton", "Robert De Niro"], "Language":["English", "Italian", "Spanish", "Latin", "Sicilian"], "imdbRating":"9.1", "imdbVotes":"64" }, "tt0468569":{ "Title":"The Dark Knight", "Year":"2008", "Runtime":"152", "Director":"Christopher Nolan", "Actors":["Christian Bale", "Heath Ledger", "Aaron Eckhart", "Michael Caine"], "Language":["English", "Mandarin"], "imdbRating":"9.0", "imdbVotes":"137" }, "tt0110912":{ "Title":"Pulp Fiction", "Year":"1994", "Runtime":"154", "Director":"Quentin Tarantino", "Actors":["Tim Roth", "Amanda Plummer", "Laura Lovelace", "John Travolta"], "Language":["English", "Spanish", "French"], "imdbRating":"8.9", "imdbVotes":"108" } } } 
 
    movies = Object.values(data.movies), 
 
    currentYear = new Date().getFullYear(); 
 

 
movies.sort((a, b) => a.Year - b.Year); 
 
let avg = movies.reduce((result, currentMovie) => { 
 
       return result + (currentYear - currentMovie.Year); 
 
      }, 0)/movies.length; 
 

 
movies.forEach(movie => console.log(`Title: ${movie.Title} (${movie.Year})`)); 
 
console.log(`Average age: ${avg}`);

來源

2017-04-18 17:12:22 Andreas

JSFiddle對象排序算法崩潰

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