需求简单示例:有String[] strArr = {"a", "b", "c", "d", "e"}; 需要得到字符串str为"a,b,c,d,e";
代码1:
StringBuilder sb = new StringBuilder();
for(int i = 0; i < strArr.length; i++){
if(i >0){
sb.append(",");
}
sb.append(strArr[i]);
}
String str = sb.toString();
System.out.println(str);
System.out.prinltn(str.length());
得到结果是:
a,b,c,d,e
9
代码2:
StringBuilder sb = new StringBuilder();
for(int i = 0; i < strArr.length; i++){
if(sb.toString().isEmpty()){
sb.append(strArr[i]);
}else{
sb.append(",").append(strArr[i]);
}
String str = sb.toString();
System.out.println(str);
System.out.println(str.length());
}
得到的结果是:
a,b,c,d,e
9