如何使用JavaScript去除字符串中的空格

js自带的方法 trim()

var str = " 6 6 ";
var str_1 = str.trim();
console.log(str_1); //6 6//输出左右侧均无空格

利用正则匹配替换

var str = " 6 6 ";
var str_1 = str.replace(/\s*/g,"");
console.log(str_1); //66

var str = " 6 6 ";
var str_1 = str.replace(/^\s*|\s*$/g,"");
console.log(str_1); //6 6//输出左右侧均无空格

var str = " 6 6 ";
var str_1 = str.replace(/^\s*/,"");
console.log(str_1); //6 6 //输出右侧有空格左侧无空格

var str = " 6 6 ";
var str_1 = str.replace(/(\s*$)/g,"");
console.log(str_1); // 6 6//输出左侧有空格右侧无空格