How do I test which class an object is in Objective-C?
How do I test whether an object is an instance of a particular 开发者_如何学编程class in Objective-C? Let's say I want to see if object a is an instance of class b, or class c, how do I go about doing it?
To test if object is an instance of class a:
[yourObject isKindOfClass:[a class]]
// Returns a Boolean value that indicates whether the receiver is an instance of
// given class or an instance of any class that inherits from that class.
or
[yourObject isMemberOfClass:[a class]]
// Returns a Boolean value that indicates whether the receiver is an instance of a
// given class.
To get object's class name you can use NSStringFromClass
function:
NSString *className = NSStringFromClass([yourObject class]);
or c-function from objective-c runtime api:
#import <objc/runtime.h>
/* ... */
const char* className = class_getName([yourObject class]);
NSLog(@"yourObject is a: %s", className);
EDIT: In Swift
if touch.view is UIPickerView {
// touch.view is of type UIPickerView
}
You also can use
NSString *className = [[myObject class] description];
on any NSObject
What means about isKindOfClass in Apple Documentation
Be careful when using this method on objects represented by a class cluster. Because of the nature of class clusters, the object you get back may not always be the type you expected. If you call a method that returns a class cluster, the exact type returned by the method is the best indicator of what you can do with that object. For example, if a method returns a pointer to an NSArray object, you should not use this method to see if the array is mutable, as shown in the following code:
// DO NOT DO THIS!
if ([myArray isKindOfClass:[NSMutableArray class]])
{
// Modify the object
}
If you use such constructs in your code, you might think it is alright to modify an object that in reality should not be modified. Doing so might then create problems for other code that expected the object to remain unchanged.
If you want to check for a specific class then you can use
if([MyClass class] == [myClassObj class]) {
//your object is instance of MyClass
}
if you want to get the name of the class simply call:-
id yourObject= [AnotherClass returningObject];
NSString *className=[yourObject className];
NSLog(@"Class name is : %@",className);
You can also check run time. Put one breakpoint in code and inside (lldb) console write
(lldb) po [yourObject class]
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