<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>字符串常用方法</title>
</head>
<body>
<script>
let strA = "西湖";
let strB = "歌舞";
let strC = "几时休";
// 1.charAt() 传入下角标(从0开始),然后获取字符串队形下标的字符
let r1 = strA.charAt(1); // '湖'
console.log("TCL: r1", r1) // TCL: r1 湖
// 2.search() 传入要查找的字符串(或者字符) 返回对应的下标志,找不到返回-1
let r2 = strC.search("休"); // 2
console.log("TCL: r2", r2) // TCL: r2 2
//3.concat() //拼接字符串,两个或者多个
let r3 = strC.concat(strB) // '几时休歌舞'
console.log("TCL: r3", r3) // TCL: r3 几时休歌舞
// 4 .toString() 把整数或者小数转换成字符串 s.toString()
let num = 123.5
let r4 = num.toString() // '123.5'
console.log("TCL: r4", r4, typeof (r4)) // TCL: r4 123.5 string
// 5.String() 也是转化成字符串 String(s);
let r5 = num.toString() // '123.5'
console.log("TCL: r5", r5, typeof (r5)) // TCL: r5 123.5 string
// 6.indexOf() 传入要查找的字符串首次出现的位置(或者字符) 返回对应的下标志,找不到返回-1
let r6 = strC.indexOf('时')
console.log("TCL: r6", r6) // TCL: r6 1
// 7.substr() 用于截取字符串
let s7 = "gahane";
let ss7 = s7.substr(1, 3); // 参数1从第几个位置开始,截取几个字符
console.log("TCL: ss7", ss7) // TCL: ss7 aha
//8.substring() 用于截取字符串
let s8 = "zhongwuchidehao"
let ss8 = s8.substring(5, 9); // 从哪开始到哪结束 不包含末尾的字符
console.log("TCL: ss8", ss8) // TCL: ss8 wuch
// 9.split() 传入规则,按照规则拆分字符串,返回一个数组
let Str9 = "I, am, a, panda, I, love, China"
let arr9 = Str9.split(", ");
console.log("TCL: arr9", arr9) // TCL: arr9 (7) ["I", "am", "a", "panda", "I", "love", "China"]
// 10.replace() 替换字符中相应文字
let Str10 = "明天放假,不可能";
let r10 = Str10.replace("不可能", "真的"); //参数1被替换,参数2要替换
console.log("TCL: r10", r10) // 明天放假,真的
let str10 = '2015-01-02';
// 想要全局替换，需要加上正则全局标识 /xxx/g， 2015-01-02 》 2015/01/02
let R10 = str10.replace(/-/g, '/')
console.log("TCL: R10", R10) // TCL: R10 2015/01/02
// 11.String.fromCharCode() //传入ASCII码值,返回相应字符
let str11 = 65
let r11 = String.fromCharCode(str11)
console.log("TCL: r11", r11) // TCL: r11 A
// 12.charCodeAt() 返回字符的ASCII值
let str12 = 'A'
let r12 = str12.charCodeAt()
console.log("TCL: r12", r12) // TCL: r12 65
// 13. toUpperCase() 全部转换成大写
let str13 = 'abc'
let r13 = str13.toUpperCase()
console.log("TCL: r13", r13) // TCL: r13 ABC
// 14. toLowerCase() 转换成小写 "Abc".toUpperCase
let str14 = 'ABC'
let r14 = str14.toLowerCase()
console.log("TCL: r14", r14) // TCL: r14 abc
//利用ASCII码封装加密字符
function setSecret(str) {
let result = "";
for (let i = 0; i < str.length; i++) {
let code = str[i].charCodeAt();
result = result + code + ","
}
return result.substr(0, result.length - 1)
}
console.log(setSecret("侯金明6傻逼")); // 20399,37329,26126,54,20667,36924
function operateSecret(str) {
let result = "";
let oldStr = str.split(",");
for (let i = 0; i < oldStr.length; i++) {
result = result + String.fromCharCode(oldStr[i]);
}
return result;
}
console.log(operateSecret("20399,37329,26126,54,20667,36924")); // 侯金明6傻逼
</script>
</body>
</html>
https://blog.csdn.net/jnx1142410525/article/details/63313689
https://www.cnblogs.com/guoyeqiang/p/8178336.html
