const text = 'helloThereMister'; const result = text.replace(/([A-Z])/g， " $1"); const finalResult = result.charAt(0).toUpperCase() + result.slice(1); console.log (finalResult);

第一个字母大写——举个例子。注意“$1”中的空格。

当然，如果第一个字母已经大写了，你就有多余的空间可以删除。

没有副作用的例子。

function camel2title(camelCase) {
  // no side-effects
  return camelCase
    // inject space before the upper case letters
    .replace(/([A-Z])/g, function(match) {
       return " " + match;
    })
    // replace first char with upper case
    .replace(/^./, function(match) {
      return match.toUpperCase();
    });
}

在ES6

const camel2title = (camelCase) => camelCase
  .replace(/([A-Z])/g, (match) => ` ${match}`)
  .replace(/^./, (match) => match.toUpperCase())
  .trim();

此解决方案也适用于不在[A-Z]范围内的其他Unicode字符。例如:Ä， Ö， Å。

let camelCaseToTitleCase = (s) => (
  s.split("").reduce(
    (acc, letter, i) => (
      i === 0 || console.log(acc, letter, i)
        ? [...acc, letter.toUpperCase()] 
        : letter === letter.toUpperCase()
        ? [...acc, " ", letter]
        : [...acc, letter] 
    ), []
  ).join("")
)

const myString = "ArchipelagoOfÅland"
camelCaseToTitleCase(myString)

使用JS的String.prototype.replace()和String.prototype.toUpperCase()

const str = "thisIsATestString"; const res = str.replace (/ ^ [a - z] | [a - z] / g (c i) = >(我吗?": "") + c.toUpperCase()); console.log (res);// "This Is A Test String"

卧底C程序员。如果你像我一样想保留首字母缩略词，不想看神秘的模式，那么你可能会喜欢这个:

function isUpperCase (str) {
  return str === str.toUpperCase()
}

export function camelCaseToTitle (str) {
  for (let i = str.length - 1; i > 0; i--) {
    if (!isUpperCase(str[i - 1]) && isUpperCase(str[i])) {
      str = str.slice(0, i) + ' ' + str.slice(i)
    }
  }
  return str.charAt(0).toUpperCase() + str.slice(1)
}

HTTPRequest_ToServer-AndWaiting --> HTTP Request To Server And Waiting

function toSpaceCase(str) { return str .replace(/[-_]/g, ' ') /* * insert a space between lower & upper * HttpRequest => Http Request */ .replace(/([a-z])([A-Z])/g, '$1 $2') /* * space before last upper in a sequence followed by lower * XMLHttp => XML Http */ .replace(/\b([A-Z]+)([A-Z])([a-z])/, '$1 $2$3') // uppercase the first character .replace(/^./, str => str.toUpperCase()) .replace(/\s+/g, ' ') .trim(); } const input = 'HTTPRequest_ToServer-AndWaiting'; const result = toSpaceCase(input); console.log(input,'-->', result)