之后如何大写字符串的所有字符。比如移动键盘

Question

我的要求不仅仅是将字符串的第一个字符大写，还有一个段落，我想将每个字符串的第一个字符大写，就像移动设备键盘一样。

我已经尝试了以下解决方案，但无法满足我的要求：

$('#test').blur(function(event) {
 var value = $(this).val();

 var output = "";

 output = value.charAt(0).toUpperCase() + value.slice(1);

});

上面的代码只对第一个字符大写。

样本输入：

lorem ipsum只是印刷和排版行业的虚拟文本。自16世纪以来，lorem ipsum一直是行业标准的虚拟文本，当时一位不知名的印刷商拿起一个打印工具，将其拼凑成一本打印样本书。就是这样！

预期产出：

Lorem Ipsum只是印刷和排版行业的虚拟文本。自16世纪以来，Lorem Ipsum一直是行业标准的虚拟文本，当时一位不知名的印刷商拿起一个打印工具，将其拼凑成一本打印样本书。就是这样！

Answer 1

您可以使用String#replace（）方法与以下正则表达式进行匹配：

/\.\s*\w/

与自定义替换回调结合使用，该回调将匹配的字符串大写以实现此目的。这里的基本思想是将直接跟在句号后面的第一个字母的任何子字符串大写（即\.）。正则表达式还考虑在句号和下一个字母字符（即\w）之间出现零个或多个空格（即\s*）的情况：

var input = "Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.That's it!";

var result = input.replace(/\.\s*\w/, function(match) {
  return match.toUpperCase();
});

console.log('Regular expression based approach', result);

Answer 2

试试这个

js prettyprint-override">var input = "Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.That's it!";
    
console.log( input.charAt(0).toUpperCase() + input.slice(1))

Answer 3

可以使用正则表达式：匹配字符串的开头或后跟空格的句点，然后匹配字母字符，并使用替换函数对该字符调用toUpperCase。还要正确替换？和后面的字母s以及，使用字符集[.？！]：

const input = `lorem ipsum is simply dummy text of the printing and typesetting industry. lorem ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.that's it!`;
const cleaned = input.replace(
  /(^|\[.?!] *)([a-z])/g,
  (_, g1, g2) => g1 + g2.toUpperCase()
);
console.log(cleaned);