在这里,单行代码存档字母第一字母资本使用JS

yourstring?.charAt(0)?.toUpperCase() + yourstring?.slice(1).toLocaleLowerCase()

var a = "this is a test"
console.log(a.replace(/^[a-z]/g, txt => txt.toUpperCase()));

/*
 * As terse as possible, assuming you're using ES version 6+
 */
var upLetter1=s=>s.replace(/./,m=>m.toUpperCase());

console.log(upLetter1("the quick brown fox jumped over the lazy dog."));
//\\ The quick brown fox jumped over the lazy dog. //\\

var nameP = prompt("please enter your name");
var nameQ = nameP.slice(0,1);
var nameR = nameP.slice(1,100);
nameQ = nameQ.toUpperCase();
nameP = nameQ + nameR;
console.log("Hello! " + nameP);

出口:

Hello! Alex

您可以使用下面的常规表达式:

return string1.toLowerCase().replace(/^[a-zA-z]|\s(.)/ig, L => L.toUpperCase());

简单的ES6合成与模板链

const capitalize = (str) => { return `${str[0].toUpperCase()}${str.slice(1)}` // return str[0].toUpperCase() + str.slice(1) // without template string } console.log(capitalize(“这是一个测试”)); console.log(capitalize(“埃菲尔塔”)); console.log(capitalize(“/index.html”)); /* “这是一个测试” → “这是一个测试” “埃菲尔塔” → “埃菲尔塔” “/index.html” → “/inde”