Add a variable to a class instance at runtime: Difference between revisions

Content added Content deleted
(jq)
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#import <objc/runtime.h>
#import <objc/runtime.h>


static void *fooKey = &fooKey; // one way to define a unique key is a pointer variable that points to itself
static char fooKey;


int main (int argc, const char *argv[]) {
int main (int argc, const char *argv[]) {
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// set
// set
objc_setAssociatedObject(e, &fooKey, @1, OBJC_ASSOCIATION_RETAIN);
objc_setAssociatedObject(e, fooKey, @1, OBJC_ASSOCIATION_RETAIN);


// get
// get
NSNumber *associatedObject = objc_getAssociatedObject(e, &fooKey);
NSNumber *associatedObject = objc_getAssociatedObject(e, fooKey);
NSLog(@"associatedObject: %@", associatedObject);
NSLog(@"associatedObject: %@", associatedObject);


Retrieved from "https://rosettacode.org/wiki/Add_a_variable_to_a_class_instance_at_runtime"