Javascript - 打印包含多个对象的数组中的所有名称[关闭]

Posted 2023-02-22

【中文标题】Javascript - 打印包含多个对象的数组中的所有名称[关闭]

【英文标题】：Javascript - print all names in array containing multiple objects [closed]

【发布时间】：2020-01-15 00:28:35

【问题描述】：

所以我是 javascript 和一般编程的新手，我在下面有一组对象。我正在尝试生成并打印一个数组，其中包含所有考试成绩为 80 或更高的学生的全名（名字和姓氏用“”分隔）。格式有点像 ['James Johnson'、'Stephanie Ottesen'、'Leonard Arvan'、'Beverly Mott'、'Beatrice Jaco']。

我已经创建了一个单独的数组，但是我无法弄清楚如何只访问数组中的某些对象并将它们添加到我的新数组中。通过谷歌搜索，我遇到了 .map()、.reduce() 和 .filter() 方法，但我正在努力弄清楚如何采用这些方法并将它们格式化到我的程序中。任何帮助或参考将不胜感激。

let students = [fname: "Jane", lname: "Brazier", snum: "100366942", agrade: 67.59127376966494, tgrade: 64.86530868914188, egrade: 70.52944558104066, fname: "Ricardo", lname: "Allen", snum: "100345641", agrade: 65.80370345301014, tgrade: 75.40211705841241, egrade: 55.39348896202821, fname: "Mary", lname: "Hernandez", snum: "100221207", agrade: 71.20761408935981, tgrade: 71.37529197926764, egrade: 75.82038980457698, fname: "James", lname: "Johnson", snum: "100200842", agrade: 72.5791318299902, tgrade: 81.65883679807183, egrade: 85.19664228946989, fname: "Stephanie", lname: "Ottesen", snum: "100225067", agrade: 88.19738810849226, tgrade: 84.68339894849353, egrade: 82.23947265645927, fname: "Martin", lname: "Conway", snum: "100358379", agrade: 71.28759059295344, tgrade: 79.13194908266965, egrade: 77.61880623797336, fname: "Andrew", lname: "Weaver", snum: "100376243", agrade: 70.01798139244363, tgrade: 78.64811561086252, egrade: 78.68650242850617, fname: "Rhonda", lname: "Ford", snum: "100296902", agrade: 56.14580882764524, tgrade: 63.9209865108888, egrade: 60.186613967770334, fname: "Leonard", lname: "Arvan", snum: "100220616", agrade: 80.67865525396981, tgrade: 92.73557717342663, egrade: 88.32126970338336, fname: "William", lname: "Culler", snum: "100307637", agrade: 65.75251699043244, tgrade: 62.18172136246404, egrade: 63.065185542933094, fname: "David", lname: "Nakasone", snum: "100353719", agrade: 62.63260239883763, tgrade: 58.352794766947866, egrade: 59.80461902691901, fname: "Maria", lname: "Young", snum: "100311331", agrade: 70.13767021264486, tgrade: 76.09348747016176, egrade: 79.99207130929622, fname: "Beverly", lname: "Mott", snum: "100325579", agrade: 83.08140516644137, tgrade: 94.80666640692787, egrade: 85.15875656837004, fname: "Patrick", lname: "Francis", snum: "100257773", agrade: 66.79534616079296, tgrade: 47.744928296560076, egrade: 64.05723052865763, fname: "Tracy", lname: "Bonds", snum: "100233277", agrade: 70.2289028670531, tgrade: 65.32258294210156, egrade: 77.04816321925091, fname: "Richard", lname: "Akers", snum: "100216705", agrade: 52.446722363991015, tgrade: 49.205597783687374, egrade: 53.72940974941982, fname: "Beatrice", lname: "Jaco", snum: "100233935", agrade: 81.89338938644417, tgrade: 71.05459078971688, egrade: 83.08235397281308, fname: "Guy", lname: "Wendelin", snum: "100336379", agrade: 68.17788319655493, tgrade: 63.82273085525137, egrade: 68.31559946786807, fname: "Logan", lname: "Olsen", snum: "100265736", agrade: 59.89037739094347, tgrade: 71.76550299333657, egrade: 64.61665695830132, fname: "Gene", lname: "Jeanlouis", snum: "100341666", agrade: 74.16481515505846, tgrade: 68.20592386917109, egrade: 78.25975050135006]

let studentNames = [];

【问题讨论】：

为什么不选择一个，比如Array#filter 并查看描述和示例。如果您有问题，请尝试并添加问题。

你试过什么？至少给我们看一个例子，否则我们只会假设你要求我们为你做功课。

如果您坚持实施也没关系，但请将您的努力发布到问题中。你甚至不需要过滤、映射或减少。一个简单的for 循环遍历数组 -> 检查if (array[i].grade > 80) -> push 输出数组的全名。

【参考方案1】：

仅提取具有Array.filter 的80 或更高年级的学生。 使用Array.map 将剩余学生映射到新格式。

结果：

let students = [
  fname: "Jane",
  lname: "Brazier",
  snum: "100366942",
  agrade: 67.59127376966494,
  tgrade: 64.86530868914188,
  egrade: 70.52944558104066
, 
  fname: "Ricardo",
  lname: "Allen",
  snum: "100345641",
  agrade: 65.80370345301014,
  tgrade: 75.40211705841241,
  egrade: 55.39348896202821
, 
  fname: "Mary",
  lname: "Hernandez",
  snum: "100221207",
  agrade: 71.20761408935981,
  tgrade: 71.37529197926764,
  egrade: 75.82038980457698
, 
  fname: "James",
  lname: "Johnson",
  snum: "100200842",
  agrade: 72.5791318299902,
  tgrade: 81.65883679807183,
  egrade: 85.19664228946989
, 
  fname: "Stephanie",
  lname: "Ottesen",
  snum: "100225067",
  agrade: 88.19738810849226,
  tgrade: 84.68339894849353,
  egrade: 82.23947265645927
, 
  fname: "Martin",
  lname: "Conway",
  snum: "100358379",
  agrade: 71.28759059295344,
  tgrade: 79.13194908266965,
  egrade: 77.61880623797336
, 
  fname: "Andrew",
  lname: "Weaver",
  snum: "100376243",
  agrade: 70.01798139244363,
  tgrade: 78.64811561086252,
  egrade: 78.68650242850617
, 
  fname: "Rhonda",
  lname: "Ford",
  snum: "100296902",
  agrade: 56.14580882764524,
  tgrade: 63.9209865108888,
  egrade: 60.186613967770334
, 
  fname: "Leonard",
  lname: "Arvan",
  snum: "100220616",
  agrade: 80.67865525396981,
  tgrade: 92.73557717342663,
  egrade: 88.32126970338336
, 
  fname: "William",
  lname: "Culler",
  snum: "100307637",
  agrade: 65.75251699043244,
  tgrade: 62.18172136246404,
  egrade: 63.065185542933094
, 
  fname: "David",
  lname: "Nakasone",
  snum: "100353719",
  agrade: 62.63260239883763,
  tgrade: 58.352794766947866,
  egrade: 59.80461902691901
, 
  fname: "Maria",
  lname: "Young",
  snum: "100311331",
  agrade: 70.13767021264486,
  tgrade: 76.09348747016176,
  egrade: 79.99207130929622
, 
  fname: "Beverly",
  lname: "Mott",
  snum: "100325579",
  agrade: 83.08140516644137,
  tgrade: 94.80666640692787,
  egrade: 85.15875656837004
, 
  fname: "Patrick",
  lname: "Francis",
  snum: "100257773",
  agrade: 66.79534616079296,
  tgrade: 47.744928296560076,
  egrade: 64.05723052865763
, 
  fname: "Tracy",
  lname: "Bonds",
  snum: "100233277",
  agrade: 70.2289028670531,
  tgrade: 65.32258294210156,
  egrade: 77.04816321925091
, 
  fname: "Richard",
  lname: "Akers",
  snum: "100216705",
  agrade: 52.446722363991015,
  tgrade: 49.205597783687374,
  egrade: 53.72940974941982
, 
  fname: "Beatrice",
  lname: "Jaco",
  snum: "100233935",
  agrade: 81.89338938644417,
  tgrade: 71.05459078971688,
  egrade: 83.08235397281308
, 
  fname: "Guy",
  lname: "Wendelin",
  snum: "100336379",
  agrade: 68.17788319655493,
  tgrade: 63.82273085525137,
  egrade: 68.31559946786807
, 
  fname: "Logan",
  lname: "Olsen",
  snum: "100265736",
  agrade: 59.89037739094347,
  tgrade: 71.76550299333657,
  egrade: 64.61665695830132
, 
  fname: "Gene",
  lname: "Jeanlouis",
  snum: "100341666",
  agrade: 74.16481515505846,
  tgrade: 68.20592386917109,
  egrade: 78.25975050135006
];

const result = students
  .filter(student => student.egrade >= 80)
  .map(student => `$student.fname $student.lname`);
  
console.log(result);