如何在字符串中插入字符

Question

比如有字符串
String s = "aa,1,2,3"; 我想在每个,后插入一个字符X 就是处理后成
aa,x1,x2,x3如何处理？
谢谢

Answer 1

        String s = "aa,1,2,3";
        String out=s.replace(",",",x");
        System.out.println("result:"+out);

Answer 2

String s = "aa,1,2,3";
        String res=s.replace(",",",x");
        System.out.println("result:"+res);

Answer 3

        String s = "aa,1,2,3";
        String res=s.replaceAll(",",",x");
        System.out.println("result:"+res);