1.substr(start,length) 抽取从 start 下标开始的指定数目的字符
stringObject.substr(start,length)
var str = "hello world";
var a = str.substr(0,3);
console.log(a) //hel
2.substring(start,end) //不接受负数
slice(start,end)
提取两个下标之间的字符
特点:不包含最后一项
var str = "hello";
var b = str.substring(1,4);
console.log(b); //ell
3.charAt(index); 返回指定位置的字符
stringObject.charAt(index)
var str= "hello";
var a = str.charAt(1);
console.log(a); //e;
4.split(); 把一个字符串分割成字符串数组
stringObject.split(separator,howmany)
| 参数 |
描述 |
| separator |
必需字符串或正则表达式,从从该参数指定的地方分割 |
| howmany |
可选 |
var str = "hello";
var a = str.split("");
console.log(a); //["h","e","l","l","0"]
var str = "hello";
var a = str.split("",3);
console.log(a); //["h","e","l"]
5.match(); 方法可在字符串内检索指定的值，或找到一个或多个正则表达式的匹配
var str="hello world 312312";
var a = str.match(/\d+/g);
console.log(a); //["312312"]
