不是說可以拼接嘛？為什么不能拼接啊
public?class?HelloWorld?{
????public?static?void?main(String[]?args)?{
????????
???????//?創(chuàng)建一個(gè)StringBuilder對(duì)象，用來存儲(chǔ)字符串
StringBuilder?hobby=new?StringBuilder("愛慕課");
StringBuilder?hobby1=new?StringBuilder("imooc");
????????
System.out.println(hobby+hobby1);
}
}
2017-04-13
這樣就行了System.out.println(hobby+""+hobby1);
2017-03-28
hobby hobby1是StringBuilder類的具體對(duì)象 ，對(duì)象怎么拼接對(duì)象，你要是都用? String hobby="愛慕課"；這樣定義字符串類型就可以拼接了。