上面的答案很简洁，但它不能处理所有的边缘情况。对于任何需要更强大的实用程序的人，没有任何外部依赖:

function camelCase(str) {
    return (str.slice(0, 1).toLowerCase() + str.slice(1))
      .replace(/([-_ ]){1,}/g, ' ')
      .split(/[-_ ]/)
      .reduce((cur, acc) => {
        return cur + acc[0].toUpperCase() + acc.substring(1);
      });
}

function sepCase(str, sep = '-') {
    return str
      .replace(/[A-Z]/g, (letter, index) => {
        const lcLet = letter.toLowerCase();
        return index ? sep + lcLet : lcLet;
      })
      .replace(/([-_ ]){1,}/g, sep)
}

// All will return 'fooBarBaz'
console.log(camelCase('foo_bar_baz'))
console.log(camelCase('foo-bar-baz'))
console.log(camelCase('foo_bar--baz'))
console.log(camelCase('FooBar  Baz'))
console.log(camelCase('FooBarBaz'))
console.log(camelCase('fooBarBaz'))

// All will return 'foo-bar-baz'
console.log(sepCase('fooBarBaz'));
console.log(sepCase('FooBarBaz'));
console.log(sepCase('foo-bar-baz'));
console.log(sepCase('foo_bar_baz'));
console.log(sepCase('foo___ bar -baz'));
console.log(sepCase('foo-bar-baz'));

// All will return 'foo__bar__baz'
console.log(sepCase('fooBarBaz', '__'));
console.log(sepCase('foo-bar-baz', '__'));

演示在这里:https://codesandbox.io/embed/admiring-field-dnm4r?fontsize=14&hidenavigation=1&theme=dark

const toCamelCase = str =>
  str
    .replace(/[^a-zA-Z0-9]+(.)/g, (m, chr) => chr.toUpperCase())
    .replace(/^\w/, c => c.toLowerCase());

从上驼峰格式("TestString")到下驼峰格式("TestString")，而不使用正则表达式(让我们面对现实吧，正则表达式是邪恶的):

'TestString'.split('').reduce((t, v, k) => t + (k === 0 ? v.toLowerCase() : v), '');

以下是我的建议:

function toCamelCase(string) {
  return `${string}`
    .replace(new RegExp(/[-_]+/, 'g'), ' ')
    .replace(new RegExp(/[^\w\s]/, 'g'), '')
    .replace(
      new RegExp(/\s+(.)(\w+)/, 'g'),
      ($1, $2, $3) => `${$2.toUpperCase() + $3.toLowerCase()}`
    )
    .replace(new RegExp(/\s/, 'g'), '')
    .replace(new RegExp(/\w/), s => s.toLowerCase());
}

or

String.prototype.toCamelCase = function() {
  return this
    .replace(new RegExp(/[-_]+/, 'g'), ' ')
    .replace(new RegExp(/[^\w\s]/, 'g'), '')
    .replace(
      new RegExp(/\s+(.)(\w+)/, 'g'),
      ($1, $2, $3) => `${$2.toUpperCase() + $3.toLowerCase()}`
    )
    .replace(new RegExp(/\s/, 'g'), '')
    .replace(new RegExp(/\w/), s => s.toLowerCase());
};

测试用例:

describe('String to camel case', function() {
  it('should return a camel cased string', function() {
    chai.assert.equal(toCamelCase('foo bar'), 'fooBar');
    chai.assert.equal(toCamelCase('Foo Bar'), 'fooBar');
    chai.assert.equal(toCamelCase('fooBar'), 'fooBar');
    chai.assert.equal(toCamelCase('FooBar'), 'fooBar');
    chai.assert.equal(toCamelCase('--foo-bar--'), 'fooBar');
    chai.assert.equal(toCamelCase('__FOO_BAR__'), 'fooBar');
    chai.assert.equal(toCamelCase('!--foo-¿?-bar--121-**%'), 'fooBar121');
  });
});

一个超级简单的方法，使用turboCommons库:

npm install turbocommons-es5

<script src="turbocommons-es5/turbocommons-es5.js"></script>

<script>
    var StringUtils = org_turbocommons.StringUtils;
    console.log(StringUtils.formatCase('EquipmentClass', StringUtils.FORMAT_LOWER_CAMEL_CASE));
    console.log(StringUtils.formatCase('Equipment className', StringUtils.FORMAT_LOWER_CAMEL_CASE));
    console.log(StringUtils.formatCase('equipment class name', StringUtils.FORMAT_LOWER_CAMEL_CASE));
    console.log(StringUtils.formatCase('Equipment Class Name', StringUtils.FORMAT_LOWER_CAMEL_CASE));
</script>

你也可以使用StringUtils。FORMAT_CAMEL_CASE和StringUtils。FORMAT_UPPER_CAMEL_CASE生成首字母大小写的变化。

更多信息:

将字符串转换为驼峰，UpperCamelCase或lowerCamelCase

简单容易理解这段代码，希望这对你有帮助，我用下面的逻辑解决了我的问题

// This example is for React Js User

const ConverToCamelCaseString = (StringValues)=> 
{
    let WordsArray = StringValues.split(" ");
    let CamelCaseValue = '';
    for (let index = 0; index < WordsArray.length; index++) 
    {
        let singleWord = WordsArray[index];
            singleWord.charAt(0).toUpperCase();
            singleWord =singleWord.charAt(0).toUpperCase() + singleWord.slice(1);

        CamelCaseValue +=" "+singleWord;
        
    }
    CamelCaseValue = CamelCaseValue.trim();
    return CamelCaseValue;
}

下面的例子是针对核心javaScript用户的

function ConverToCamelCaseString (StringValues) 
    {
        let WordsArray = StringValues.split(" ");
        let CamelCaseValue = '';
        for (let index = 0; index < WordsArray.length; index++) 
        {
            let singleWord = WordsArray[index];
                singleWord.charAt(0).toUpperCase();
                singleWord =singleWord.charAt(0).toUpperCase() + singleWord.slice(1);

            CamelCaseValue +=" "+singleWord;
            
        }
        CamelCaseValue = CamelCaseValue.trim();
        return CamelCaseValue;
    }

console.log(ConverToCamelCaseString("this is my lower case string")); 

我希望上面的例子能解决你的问题。