class_addProperty运行时方法

static char *propertykey = nil;

NSString *getterMeth(id self, SEL _cmd) {

Ivar ivar = class_getInstanceVariable([SomeClass class],propertykey );

return object_getIvar(self, ivar);

}

void setterMeth(id self, SEL _cmd, NSString *name) {

Ivar ivar = class_getInstanceVariable([SomeClass class], propertykey);

id oldName = object_getIvar(self, ivar);

if (oldName != ame) object_setIvar(self, ivar, [name copy]);

}

int main(void) {

propertykey = "_privaName";

@autoreleasepool {

objc_property_attribute_t types = { "T", "@\"NSString\"" };

objc_property_attribute_t ownership = { "C", "" }; // C = copy

objc_property_attribute_t backIvar  = { "V", "_privateName" };

objc_property_attribute_t attrs[] = { types, ownership, backIvar };

class_addProperty([SomeClass class], "name", attrs, 3);

class_addMethod([SomeClass class], @selector(name), (IMP)nameGetter, "@@:");

class_addMethod([SomeClass class], @selector(setName:), (IMP)nameSetter, "v@:@");

id o = [SomeClass new];

NSLog(@"%@", [o name]);

[o setName:@"your Name"];

NSLog(@"%@", [o name]);

}

}