正則
去除所有空格::str = str.replace(/\s*/g,"")
去除兩頭空格::str = str.replace(/^\s*|\s*$/g,"")
去除左空格: str = str.replace( /^\s*/, “”)
去除右空格: str = str.replace(/(\s*$)/g, "")
str.trim(str)
侷限性:無法去除中間的空格
var str = " xiao ming ";
var str2 = str.trim();
console.log(str2); //xiao ming
$.trim(str)
侷限性:無法去除中間的空格
var str = " xiao ming ";
var str2 = $.trim(str)
console.log(str2); // xiao ming