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iOS Swift 2.0 Collections and Control Flow Dictionaries Recap: Dictionaries

Posted by Drew Butcher
Drew Butcher
33,160 Points

Difference between myDictionary.updateValue("yetAnotherValue", forKey: 3) and myDictionary[3] = "yetAnotherValue".

What is the difference between these two. They seem to both create or update the key value pair of myDictionary.

1 Answer

Steven Deutsch
Steven Deutsch
21,046 Points

Hey Drew Butcher,

You are correct, both are valid ways to update and create values in your dictionary. 

// Here you are creating a key,value pair directly
myDictionary[3] = "yetAnotherValue"

// Here you are using the updateValue method
myDictionary.updateValue("yetAnotherValue", forKey: 3)

//It is safer to interact with your data via methods, compared to manipulating them directly.

Good Luck

Drew Butcher
Drew Butcher
33,160 Points

Cool, so it's safer to use the method call, but which is faster?