我如何转换字符串既像'helloThere'或'helloThere'到'HelloThere'在JavaScript?


当前回答

我的分裂案例解决方案的行为方式,我想:

const splitCase = s => !s || s.indexOf(' ') >= 0 ? s :
    (s.charAt(0).toUpperCase() + s.substring(1))
        .split(/(?<=[a-z])(?=[A-Z])|(?<=[A-Z])(?=[A-Z][a-z])/g)
        .map(x => x.replace(/([0-9]+)/g,'$1 '))
        .join(' ')

输入

'a,abc,TheId,TheID,TheIDWord,TheID2Word,Leave me Alone!'
.split(',').map(splitCase)
.forEach(x => console.log(x))

输出

A
Abc
The Id
The ID
The ID Word
The ID2 Word
Leave me Alone!

由于上述函数需要在JS中使用Lookbehind,而目前Safari中还没有实现,因此我重写了实现,以不使用下面的RegEx:

const isUpper = c => c >= 'A' && c <= 'Z'
const isDigit = c => c >= '0' && c <= '9'
const upperOrDigit = c => isUpper(c) || isDigit(c)

function splitCase(s) {
    let to = []
    if (typeof s != 'string') return to
    let lastSplit = 0
    for (let i=0; i<s.length; i++) {
        let c = s[i]
        let prev = i>0 ? s[i-1] : null
        let next = i+1 < s.length ? s[i+1] : null
        if (upperOrDigit(c) && (!upperOrDigit(prev) || !upperOrDigit(next))) {
            to.push(s.substring(lastSplit, i))
            lastSplit = i
        }
    }
    to.push(s.substring(lastSplit, s.length))
    return to.filter(x => !!x)
}

其他回答

这是我的版本。它在每个小写英文字母后面的大写英文字母之前增加一个空格,如果需要,还会将第一个字母大写:

例如: This IsCamelCase——> This IsCamelCase 这是骆驼案——>这是骆驼案 This IsCamelCase123——>

  function camelCaseToTitleCase(camelCase){
    if (camelCase == null || camelCase == "") {
      return camelCase;
    }

    camelCase = camelCase.trim();
    var newText = "";
    for (var i = 0; i < camelCase.length; i++) {
      if (/[A-Z]/.test(camelCase[i])
          && i != 0
          && /[a-z]/.test(camelCase[i-1])) {
        newText += " ";
      }
      if (i == 0 && /[a-z]/.test(camelCase[i]))
      {
        newText += camelCase[i].toUpperCase();
      } else {
        newText += camelCase[i];
      }
    }

    return newText;
  }

连续大写单词的最兼容的答案是:

常量文本 = 'theKD'; const result = text.replace(/([A-Z]{1,})/g, “$1”); const finalResult = result.charAt(0).toUpperCase() + result.slice(1); 控制台.log(最终结果);

它也与KD兼容,不会将其转换为KD。

添加了另一个ES6解决方案,我更喜欢上面的一些想法。

https://codepen.io/902Labs/pen/mxdxRv?editors=0010#0

const camelize = (str) => str
    .split(' ')
    .map(([first, ...theRest]) => (
        `${first.toUpperCase()}${theRest.join('').toLowerCase()}`)
    )
    .join(' ');

这种实现需要考虑连续的大写字母和数字。

function camelToTitleCase(str) { return str .replace(/[0-9]{2,}/g, match => ` ${match} `) .replace(/[^A-Z0-9][A-Z]/g, match => `${match[0]} ${match[1]}`) .replace(/[A-Z][A-Z][^A-Z0-9]/g, match => `${match[0]} ${match[1]}${match[2]}`) .replace(/[ ]{2,}/g, match => ' ') .replace(/\s./g, match => match.toUpperCase()) .replace(/^./, match => match.toUpperCase()) .trim(); } // ----------------------------------------------------- // var testSet = [ 'camelCase', 'camelTOPCase', 'aP2PConnection', 'superSimpleExample', 'aGoodIPAddress', 'goodNumber90text', 'bad132Number90text', ]; testSet.forEach(function(item) { console.log(item, '->', camelToTitleCase(item)); });

预期的输出:

camelCase -> Camel Case
camelTOPCase -> Camel TOP Case
aP2PConnection -> A P2P Connection
superSimpleExample -> Super Simple Example
aGoodIPAddress -> A Good IP Address
goodNumber90text -> Good Number 90 Text
bad132Number90text -> Bad 132 Number 90 Text

试试这个库

http://sugarjs.com/api/String/titleize

'man from the boondocks'.titleize()>"Man from the Boondocks"
'x-men: the last stand'.titleize()>"X Men: The Last Stand"
'TheManWithoutAPast'.titleize()>"The Man Without a Past"
'raiders_of_the_lost_ark'.titleize()>"Raiders of the Lost Ark"