JS小函数-字符串的首字母大写
字符串的首字母大写,不能使用:
toUpperCase()
toLowerCase()
例子:
"string".capitalize() === "String"
"hello World".capitalize() === "Hello World"
"i love codewars".capitalize() === "I love codewars"
"This sentence is already capitalized".capitalize() === "This sentence is already capitalized"
"0123the first character of this sentence is not a letter".capitalize() === "0123the first character of this sentence is not a letter"
这次依旧没有我的答案。
1.
- String.prototype.capitalize = function () {
- let c = this.charCodeAt(0);
- if (97 <= c && c <= 122) c -= 32;
- return String.fromCharCode(c) + this.slice(1);
- }
2.
- String.prototype.capitalize = function(){
- var map = {
- a : 'A',
- b : 'B',
- c : 'C',
- d : 'D',
- e : 'E',
- f : 'F',
- g : 'G',
- h : 'H',
- i : 'I',
- j : 'J',
- k : 'K',
- m : 'M',
- n : 'N',
- o : 'O',
- p : 'P',
- q : 'Q',
- r : 'R',
- s : 'S',
- t : 'T',
- u : 'U',
- v : 'V',
- w : 'W',
- x : 'X',
- y : 'Y',
- z : 'Z'
- };
- return map[this[0]] ? map[this[0]] + this.slice(1) : this.toString();
- };
3.
- String.prototype.capitalize = function() {
- return this.replace(/^[a-z]/, c => String.fromCharCode(c.charCodeAt(0)-32))
- }
4.
- String.prototype.capitalize = function() {
- return /^[a-z]/.test(this) ? this.replace(this.charAt(0), String.fromCharCode(this.charCodeAt(0) - 32)) :
- this.toString();
- }
5.
- String.prototype.capitalize = function()
- {
- var searchArray = 'abcdefghijklmnopqrstuvwxyz';
- var replaceArray = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
- var array = this.split('');
- var index = searchArray.indexOf(array[0]);
- if (index > -1) array[0] = replaceArray[index];
- return array.join('');
- }
6.
- String.prototype.capitalize = function() {
- var alf = 'abcdefghijklmnopqrstuvwxyz';
- var alfC = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
- var self = this.split('');
- if (alf.indexOf(self[0]) != -1) {
- self[0] = alfC[alf.indexOf(self[0])];
- }
- return self.join('');
- }
7.
- String.prototype.capitalize = function() {
- if (this.charCodeAt(0) >= 97 && this.charCodeAt(0) <= 122) {
- return (String.fromCharCode(this.charCodeAt(0) - 32) + this.slice(1));
- }
-
- return this.toString();
- }
8.
- String.prototype.capitalize = function() {
- if (this.charCodeAt() < 97 || this.charCodeAt() > 122) return this.toString();
- return String.fromCharCode(this.charCodeAt() - 32) + this.substring(1);
- };