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NSRange strange behavior

开发者 https://www.devze.com 2023-02-16 19:03 出处:网络
I have strange NSRange behavior on my device (iPhone iOS 4.3). This code has a different behavior on device and simulator.

I have strange NSRange behavior on my device (iPhone iOS 4.3). This code has a different behavior on device and simulator.

for (Location *location in locationArray)
{
    NSRange range1 = [location.name rangeOfString:searchText options:NSCaseInsensitiveSearch];
    NSRange range2 = [location.streetAddress rangeOfString:searchText options:NSCaseInsensitiveSearch];
    NSRange range3 = [location.postalCode rangeOfString:searchText options:NSCaseInsensitiveSearch];

if (range.length1 > 0 | range2.length > 0 | range3.length > 0)
    [self.filteredList addObject:location];
}

If some of prop开发者_如何学JAVAerties has nil value range.lenght for that property is equal to 2 on device and zero in simulator.

Am I doing something wrong?


The Objective-C Programming Language

The value returned from a message to nil may also be valid:

  • If the method returns an object, then a message sent to nil returns 0 (nil). For example: Person *motherInLaw = [[aPerson spouse] mother]; If the spouse object here is nil, then mother is sent to nil and the method returns nil.
  • If the method returns any pointer type, any integer scalar of size less than or equal to sizeof(void*), a float, a double, a long double, or a long long, then a message sent to nil returns 0.
  • If the method returns a struct, as defined by the Mac OS X ABI Function Call Guide to be returned in registers, then a message sent to nil returns 0.0 for every field in the struct. Other struct data types will not be filled with zeros.
  • If the method returns anything other than the aforementioned value types, the return value of a message sent to nil is undefined.

It's for Mac OS X but I think it's safe to say that you should not rely on returned struct values if message target is nil.

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