JavaScript 点阵分割

Question

我有一个包含文件名及其扩展名的 Javascript 数组，例如：

let files = ["Apple.docx", "Cat.jpeg", "Moon.gif"];

我想这样做，以便将（.docx、.jpeg 和 .gif）之类的扩展名存储在另一个数组中，并且在原始数组变成：

let files = ["Apple", "Cat", "Moon"];
let extensions = ['DOCX', 'JPEG', 'GIF'];

Answer 1

您可以只使用String.split()方法。 关于扩展，您可以使用String.toUpperCase() 。

 const files = ["Apple.docx", "Cat.jpeg", "Moon.gif"]; const names = [], extensions = []; files.forEach(name => { const splitted = name.split("."); names.push(splitted[0]); extensions.push(splitted[1].toUpperCase()); }); console.log(names, extensions);

Answer 2

 const extensions = []; const files = ["Apple.docx", "Cat.jpeg", "Moon.gif"].map(x => { const idx = x.lastIndexOf("."); if (idx === -1) { extensions.push(""); return x; } extensions.push(x.substring(idx + 1).toUpperCase()); return x.substring(0, idx); }); console.log(files); console.log(extensions);

Answer 3

 let files = ["Apple.docx", "Cat.jpeg", "Moon.gif"]; extensions = files.map(e => (e.split('.')[1]).toUpperCase()) console.log(extensions)

Answer 4

尝试：

let files = ["Apple.docx", "Cat.jpeg", "Moon.gif"];
let extensions = [];
let newFiles = [];
files.map((val)=>{
    newFiles.push(val.split('.')[0]); // files name without extension
    extensions.push(val.split('.')[1]); // extensions of files.
});

Answer 5

以下是使用String.split 、 Array.reduce和Destructuring assignment的方法之一，以实现预期的 output。

 let files = ["Apple.docx", "Cat.jpeg", "Moon.gif"]; const formatFiles = files => { return files.reduce((res, file) => { //split and assign the values using destructuring assignment const [name, ext] = file.split("."); res.names.push(name); res.exts.push(ext.toUpperCase()); return res; }, {names: [], exts:[]}); } console.log(formatFiles(files));

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