根据JavaScript中的首字母对名称进行分组

假设我们有一个这样的名称数组-

const arr = ["Simon", "Mike", "Jake", "Lara", "Susi", "Blake", "James"];

我们需要编写一个包含一个这样的数组的JavaScript函数。该函数应返回具有两个属性的对象数组-

字母->名称分组的字母

名称->属于该组的名称数组

示例

为此的代码将是-

const arr = ["Simon", "Mike", "Jake", "Lara", "Susi", "Blake", "James"]; const groupNames = arr => { const map = arr.reduce((acc, val) => { let char = val.charAt(0).toUpperCase(); acc[char] = [].concat((acc[char] || []), val); return acc; }, {}); const res = Object.keys(map).map(el => ({ letter: el, names: map[el] })); return res; }; console.log(groupNames(arr));

输出结果

控制台中的输出-

[ { letter: S, names: [ Simon, Susi ] }, { letter: M, names: [ Mike ] }, { letter: J, names: [ Jake, James ] }, { letter: L, names: [ Lara ] }, { letter: B, names: [ Blake ] } ]