js 字符串

$(function(){    var str="asdfghjkl";    var resul_sub=str.substring(0,4);//截取前四个字符    console.log(resul_sub);//asdf    var str1="a|s|d|f|g|h|j|k|l";    var result_sp=str1.split('|');    console.log(typeof result_sp);    $.each(result_sp,function(n,value) {        console.log(value);//分别输出各个元素    });    //将数组转换为字符串    var arr = new Array(3);    arr[0] = "George";    arr[1] = "John";    arr[2] = "Thomas";    console.log(arr.join());//George,John,Thomas    var arr1 = new Array(3)    arr1[0] = "George"    arr1[1] = "John"    arr1[2] = "Thomas"    console.log(arr1.join("-"));//George-John-Thomas    var resul_if=str.indexOf("s");//根据字符返回下标    console.log(resul_if);//1    var resul_ch=str.charAt(2);//根据下标返回字符    console.log(resul_ch);//d})