下面是一行代码:

const camelCaseIt = string => string.toLowerCase().trim().split(/[.\-_\s]/g).reduce((string, word) => string + word[0].toUpperCase() + word.slice(1));

它根据RegExp[中提供的字符列表拆分小写字符串。\-_\s](在[]中添加更多!)并返回一个单词数组。然后，它将字符串数组缩减为一个由首字母大写的单词组成的连接字符串。由于reduce没有初始值，它将从第二个单词开始大写第一个字母。

如果你想要PascalCase，只需在reduce方法中添加一个初始空字符串，”)。

如果有人正在使用lodash，则有_.camelCase()函数。

_.camelCase('Foo Bar');
// → 'fooBar'

_.camelCase('--foo-bar--');
// → 'fooBar'

_.camelCase('__FOO_BAR__');
// → 'fooBar'

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), '');

一个有趣的方法是通过dataset属性。

函数camelize(dashString) { let el = document.createElement('div') el.setAttribute(数据——+ dashString”) 返回种(el.dataset) [0] ｝ camelize('x-element') // 'xElement'

为了有效地创建一个将字符串的大小写转换为驼峰式大小写的函数，该函数还需要首先将每个字符串转换为小写，然后再将非第一个字符串的第一个字符转换为大写字母。

我的示例字符串是:

"text That I WaNt to make cAMEL case"

对于这个问题提供的许多其他解决方案返回这个:

"textThatIWaNtToMakeCAMELCase"

我认为应该是预期的，期望的输出将是这样的，其中所有的中间字符串大写字符首先转换为小写:

"textThatIWanrtToMakeCamelCase"

这可以在不使用任何replace()方法调用的情况下完成，通过使用String.prototype.split()， Array.prototype.map()和Array.prototype.join()方法:

≤ES5版本

function makeCamelCase(str) {
  return str
    .split(' ')
    .map((e,i) => i
      ? e.charAt(0).toUpperCase() + e.slice(1).toLowerCase()
      : e.toLowerCase()
    )
    .join('')
}

makeCamelCase("text That I WaNt to make cAMEL case")
// -> "textThatIWanrtToMakeCamelCase" ✅

我将分解每一行的功能，然后以其他两种格式提供相同的解决方案——ES6格式和字符串格式。prototype方法，不过我建议不要像这样直接扩展内置的JavaScript原型。

讲解员

function makeCamelCase(str) {
  return str
    // split string into array of different words by splitting at spaces
    .split(' ')
    // map array of words into two different cases, one for the first word (`i == false`) and one for all other words in the array (where `i == true`). `i` is a parameter that denotes the current index of the array item being evaluated. Because indexes start at `0` and `0` is a "falsy" value, we can use the false/else case of this ternary expression to match the first string where `i === 0`.
    .map((e,i) => i
      // for all non-first words, use a capitalized form of the first character + the lowercase version of the rest of the word (excluding the first character using the slice() method)
      ? e.charAt(0).toUpperCase() + e.slice(1).toLowerCase()
      // for the first word, we convert the entire word to lowercase
      : e.toLowerCase()
    )
    // finally, we join the different strings back together into a single string without spaces, our camel-cased string
    .join('')
}

makeCamelCase("text That I WaNt to make cAMEL case")
// -> "textThatIWanrtToMakeCamelCase" ✅

压缩ES6+(一行程序)版本

const makeCamelCase = str => str.split(' ').map((e,i) => i ? e.charAt(0).toUpperCase() + e.slice(1).toLowerCase() : e.toLowerCase()).join('')

makeCamelCase("text That I WaNt to make cAMEL case")
// -> "textThatIWanrtToMakeCamelCase" ✅

字符串。原型方法版本

String.prototype.toCamelCase = function() {
  return this
    .split(' ')
    .map((e,i) => i
      ? e.charAt(0).toUpperCase() + e.slice(1).toLowerCase()
      : e.toLowerCase()
    )
    .join('')
}

"text That I WaNt to make cAMEL case".toCamelCase()
// -> "textThatIWanrtToMakeCamelCase" ✅

以下所有14个排列产生相同的“equipmentClassName”结果。

String.prototype.toCamelCase = function() { return this.replace(/[^a-z ]/ig, '') // Replace everything but letters and spaces. .replace(/(?:^\w|[A-Z]|\b\w|\s+)/g, // Find non-words, uppercase letters, leading-word letters, and multiple spaces. function(match, index) { return +match === 0 ? "" : match[index === 0 ? 'toLowerCase' : 'toUpperCase'](); }); } String.toCamelCase = function(str) { return str.toCamelCase(); } var testCases = [ "equipment class name", "equipment class Name", "equipment Class name", "equipment Class Name", "Equipment class name", "Equipment class Name", "Equipment Class name", "Equipment Class Name", "equipment className", "equipment ClassName", "Equipment ClassName", "equipmentClass name", "equipmentClass Name", "EquipmentClass Name" ]; for (var i = 0; i < testCases.length; i++) { console.log(testCases[i].toCamelCase()); };