Getting a comma separated string from NSArray

NSArray *arr = @[@1,@2,@3,@"abc"];
NSLog(@"%@", arr);
NSLog(@"description:%@", [arr description]);
/*
兩種方式都輸出如下，被加上換行符號
(
    1,
    2,
    3,
    abc
)
*/

改成componentsJoinedByString

NSLog(@"%@", [arr componentsJoinedByString:@","]);
//1,2,3,abc