从具有不同键的数组中按值删除项目

Question

我正在尝试创建一个从我的 JSON 文件中删除一个单词的函数。

功能：

function removeword(lang,word) {

  var farr = [];
  var count = 0;

  fs.readFile('./dictionary.json', 'utf8', (err, jsonString) => {
    var items = JSON.parse(jsonString);

    for (var i = 0; i < items.length; i++) {
      console.log(items[lang][i]);
      if (word === items[lang][i]) {
        items[lang].splice(i, 1);
      }
    }

    console.log(items);

     fs.writeFile("./dictionary.json", JSON.stringify(items), function(err){
           if (err) throw err;
           console.log('Done!');
     });

  });
}

原始 JSON：

{"en":["moon","crazy"],"pt":["macaco", "macarrão"],"es":["hola"]}

通过调用 removeword('pt', 'macaco')，这是我的期望：

{"en":["moon","crazy"],"pt":["macarrão"],"es":["hola"]}

Answer 1

您可以为给定的键在您的items数组上调用.filter() ，您可以通过。 对于数组中不是您的值的任何元素，您可以通过返回true ( v !== value ) 来保留它，否则，您可以删除它（通过返回 false）：

 const items = {"en":["moon","crazy"],"pt":["macaco", "macarrão"],"es":["hola"]}; function removeword(obj, key, value) { obj[key] = obj[key].filter(v => v !== value); } removeword(items, 'pt', 'macaco'); console.log(items); // {"en":["moon","crazy"],"pt":["macarrão"],"es":["hola"]}

如果您不想修改您的items数组（而是返回一个新的修改过的items数组），您可以使用Object.fromEntries()从[key, value]对数组创建一个新对象，您可以在其中过滤value数组，如果key匹配您传入的键：

 const items = {"en":["moon","crazy"],"pt":["macaco", "macarrão"],"es":["hola"]}; const removeword = (obj, key, value) => Object.fromEntries( Object.entries(obj).map(([k, arr]) => k === key ? [k, arr.filter(v => v !== value)] : [k, arr]) ); const result = removeword(items, 'pt', 'macaco'); console.log(result); // {"en":["moon","crazy"],"pt":["macarrão"],"es":["hola"]}

^{请参阅Object.fromEntries() 浏览器兼容性}

上面不可变方法的浏览器兼容版本会使用.reduce() ：

 const items = {"en":["moon","crazy"],"pt":["macaco", "macarrão"],"es":["hola"]}; const removeword = (obj, key, value) => Object.keys(obj).reduce((o, k) => ({...o, [k]: k === key ? obj[k].filter(v => v !== value) : obj[k]}), {}) const result = removeword(items, 'pt', 'macaco'); console.log(result); // {"en":["moon","crazy"],"pt":["macarrão"],"es":["hola"]}