用奇数分隔符将字符串中的每个单词大写(不使用正则表达式的快速解决方案)

function capitalizeFirstLetter(str) {
  function isLetter(char) {
    const code = char.charCodeAt(0);
    // Considering apostrophe (char code 39) as a letter
    return code > 64 && code < 91 || code > 96 && code < 123 || char.charCodeAt(0) === 39;
  }

  str = str.toLowerCase();

  let newStr = '';
  let processingWord = false;

  for (let i = 0; i < str.length; i += 1) {
    if (!processingWord && isLetter(str[i])) {
      processingWord = true;
      newStr += str[i].toUpperCase();
    }
    else {
      newStr += str[i];
    }

    if (processingWord && !isLetter(str[i])) {
      processingWord = false;
    }
  }

  return newStr;
}

// stack overflow -> Stack Overflow
// ping-pong -> Ping-Pong
// domino's pizza -> Domino's Pizza
// /some/path -> /Some/Path

@somethingthere有一个更紧凑(和现代)的重写方案:

let titleCase = (str => str. tolowercase()。(' ') . map(分裂 c => c. charat (0). touppercase () + c.substring(1))。加入(' ')); 文档。write(titleCase(“我是一个更小的茶壶”));

有很多方法可以实现这一点，例如，你可以尝试遍历字符串，或使用JavaScript内置的split()， map()和join()

我更喜欢使用正则表达式与替换方法，这是可用的字符串

capitalize = (str) =>  {
  return str.replace(/\b[a-z]/g, (letter) => letter.toUpperCase(););
}

使用\b边界匹治程序和[a-z]字符类标识，并使用回调函数将其替换为字母的大写版本。 更高效的 因为它只在字符串中的字符上迭代一次，并且它使用正则表达式来标识要大写的字母，这通常比使用循环和字符串操作实现相同的逻辑更快。

ECMAScript 6版本:

const toTitleCase =(短语)=> { 返回的短语 .toLowerCase () .split (' ') .map(word => word. charat (0).toUpperCase() + word.slice(1)) . join (' '); }; let result = toTitleCase('maRy have a lIttLe LaMb'); console.log(结果);

function titleCase(str) { //First of all, lets make all the characters lower case let lowerCaseString = ""; for (let i = 0; i < str.length; i++) { lowerCaseString = lowerCaseString + str[i].toLowerCase(); } //Now lets make the first character in the string and the character after the empty character upper case and leave therest as it is let i = 0; let upperCaseString = ""; while (i < lowerCaseString.length) { if (i == 0) { upperCaseString = upperCaseString + lowerCaseString[i].toUpperCase(); } else if (lowerCaseString[i - 1] == " ") { upperCaseString = upperCaseString + lowerCaseString[i].toUpperCase(); } else { upperCaseString = upperCaseString + lowerCaseString[i]; } i = i + 1; } console.log(upperCaseString); return upperCaseString; } titleCase("hello woRLD");

ECMA2017或ES8

const titleCase = (string) => { return string .split(' ') .map(word => word.substr(0,1).toUpperCase() + word.substr(1,word.length)) .join(' '); }; let result = titleCase('test test test'); console.log(result); Explanation: 1. First, we pass the string "test test test" to our function "titleCase". 2. We split a string on the space basis so the result of first function "split" will be ["test","test","test"] 3. As we got an array, we used map function for manipulation each word in the array. We capitalize the first character and add remaining character to it. 4. In the last, we join the array using space as we split the string by sapce.