objective c - Is there a way to dynamically allocate or assign values to ivars of a class at runtime in Cocoa / Cocoa Touch? -


i'm sure can dynamically determine ivars of class @ run time. there way allocate determined ivars during run time? tia..

the short answer , 1 want is:
[obj setvalue:@"woof" forkey:@"dog"];

and ramblings...

you can using runtime find of ivars of class with:

ivar * class_copyivarlist(class cls, unsigned int *outcount)

eg:

id someobj; //assigned elsewhere unsigned int count = 0; ivar * ivarlist = class_copyivarlist([someobj class],&count); for(;count>0;count--) {     ivar testvar = ivarlist[count];      //do test ivar } free(ivarlist);

i sure wouldn't ever want except perhaps in debugging scenario... introspecting private frameworks etc.

or if know name of ivar can use:
ivar object_setinstancevariable(id obj, const char *name, void *value) or more objc way of [obj setvalue: @"woof" forkey:@"dog"] fail through setting ivar.

what potentially do, , have had in past introspect properties list:

with analogous call to: objc_property_t * class_copypropertylist(class cls, unsigned int *outcount) can useful copying unknown objects, , debugging.


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