ios - stringByReplacingOccurrencesOfString : doesn't work

Question

我希望我的输出是“23”，但它仍然显示“123”。

NSString *valorTextField = [[NSString alloc] initWithFormat:@"123"];
    [valorTextField stringByReplacingOccurrencesOfString:@"1" withString:@""];
    NSLog(@"%@", valorTextField);

Answer 1

stringByReplacingOccurrencesOfString 返回一个新字符串:

NSString *valorTextField = [[NSString alloc] initWithFormat:@"123"];
NSString *replaced = [valorTextField stringByReplacingOccurrencesOfString:@"1" withString:@""];
NSLog(@"%@", replaced);

或者，您可以使用 NSMutableString 并使用replaceOccurrencesOfString:withString:options:range: 方法。