假如不清楚多少个字符,只知道是2的倍数,我该怎么做啊???
追答String str2 = "1234567890";
String reg2 = "";
String res = "";
for(int i = 0; i < str2.length() / 2; i++)
{
reg2 += "(\\d{2})";
res += "$" + (i + 1);
if(i != str2.length() / 2 - 1)
{
res += "#";
}
}
System.out.println(reg2);
System.out.println(res);
System.out.println(str2.replaceAll(reg2, res));