以下是将一长串数字分组用逗号隔开,每三个一组,转化为字符串.
例如:
2345678--->2,345,678
23--->23
private static String convert(long space) {
String str = String.valueOf(space);
StringBuilder builder = new StringBuilder(str);
str = builder.reverse().toString();
StringBuilder stringBuilder = new StringBuilder();
for (int i = 0; i < str.length(); i++) {
if (i%3==0) {
//防越界&保留最高位
if (i+3>str.length()){
stringBuilder.append(str.substring(i));
break;
}
stringBuilder.append(str.substring(i, i + 3) + ",");
}
}
str = stringBuilder.reverse().toString();
//消除字符串长度为3的倍数时多出的','
if (str.charAt(0)==','){
str = str.substring(1);
}
return str;
}
还可以再继续优化,间隔,分隔符.....哎呀,肚子好疼,再见!