闲来无事,巩固下基础...
字符串:
字符串拆分split()
字符串截取slice()
字符串替换replace()
var str = "test,entity";
console.log("*******字符串*********");
//字符串拆分成数组
console.log("split:",str.split(","));
//字符串截取
//substr(开始索引,截取位数),可从尾部截取,索引负数,末尾-1
//slice 可省略第二个参数,从指定位置截到最后
console.log("substr1:",str.substr(5,3));
console.log("substr2:",str.substr(-3,3));
console.log("slice1:",str.slice(0,4));
console.log("slice2:",str.slice(4));
console.log("slice3:",str.slice(-6));
//查找某个字符串索引,indexOf为首次出现,lastIndexOf末次出现,找不到则为-1
//可设置第二个参数从指定位置开始查找,indexOf从左到右,lastIndexOf从右到左
console.log("indexOf:",str.indexOf("t"));
console.log("indexOf:",str.indexOf("t",5));
console.log("lastIndexOf:",str.lastIndexOf("t"));
console.log("lastIndexOf:",str.lastIndexOf("t",2));
//字符串查找,返回索引,没有则-1,可使用正则
console.log("serach1:",str.search("test"));
console.log("serach2:",str.search(/[1-9]/g));
// 字符串替换 ("被替换","替换")
console.log("replace:",str.replace("entity","string"));
//字符串拼接 可连接多个,等同字符串中加号用法
console.log("concat:",str.concat(",app",",web"));
var arr = ["a","b","c"];
//数组转字符串,可指定间隔符
console.log("join1:",arr.join());
console.log("join2:",arr.join("--"));
//toString 逻辑值转换为字符串
console.log("toString1:",arr.toString());
console.log("toString2:",true.toString());
var obj = {"name":"jiangnan"};
//json类型转字符串
console.log("stringify:",JSON.stringify(obj));
//解析
var objStr =JSON.stringify(obj);
console.log("parse:",JSON.parse(objStr));
运行如下:
扫描二维码关注公众号,回复:
10473071 查看本文章
数组:
查找元素位置indexOf()
删除末尾元素pop()
删除首个元素shift()
添加新元素push()
连接新数组concat()
对象:
合并对象Object.assign(obj1, obj2, obj3)