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iOS Build a Blog Reader iPhone App Data Modeling Using a Custom Class

J R
J R
2,037 Points
Posted by J R
J R
2,037 Points

objectForKey vs valueForKey

Hi all,

I am a little confused with this part of the code on this video: BlogPost *blogPost = [BlogPost blogPostWithTitle:[bpDictionary objectForKey:@"title"]];

Why use objectForKey and not valueForKey in this case?

1 Answer

Gabe Nadel
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STAFF
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Gabe Nadel
Treehouse Guest Teacher
Gabe Nadel
.a{fill-rule:evenodd;}techdegree
Gabe Nadel
Treehouse Guest Teacher

In this case, you could actually use either valueForKey or objectForKey, they'll both work. They have some similarities and differences and there is plenty to read on the subject - I'll let you google that if you are interested.

However, on key difference is that objectForKey is actually an NSDictionary (whereas valueForKey is more general) and since the bpDictionary instance variable is of the class NSDictionary, that is the preferred one to use here.