帮忙解释下这个正则替换

Question

 var _loc_3= /-""-/gi;
 var p="ZT5B-2UG5-5710-4N3P-2226-5O3C-2942-0Q05-6L10-376F-5J21-5M/4249";
 p=p.replace(_loc_3,"");
 alert(p);

Answer 1

ZT5B-2UG5-5710-4N3P-2226-5O3C-2942-""-0Q05-6L10-376F-5J21-5M/4249
把红色的替换成""

Answer 2

那个字符串里没有符合-""-这个规则的 当然没结果了 var _loc_3= /-""-/gi; //全局匹配-""- 
 var p="ZT5B-2UG5-5710-4N3P-2226-5O3C-2942-0Q05-6L10-376F-5J21-5M/4249";
 var newP ='ZT5B-""-2UG5-5710-4N3P-2226-5O3C-2942-0Q05-6L10-376F-5J215M/4249';
 p=p.replace(_loc_3,"");
 alert(p); //p没有变
 newP =newP.replace(_loc_3,"");
 alert(newP);// 结果 ZT5B2UG5-5710-4N3P-2226-5O3C-2942-0Q05-6L10-376F-5J215M/4249