使用iOS,如何检查URL是否为空

Question

我正在加载一个JSON,但我想检查"URL": "",json中是否为空,有时ID是空的,我该怎么检查？

if(URL == HOW TO CHECK IF EMPTY?)
{

}
else
{

}

错误:

*** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSArrayI objectAtIndex:]: index 0 beyond bounds for empty array'
*** First throw call stack:

Answer 1

嗯,试试吧

if ([URL isEqualToString:@"The URL?"]) {