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iOS

Posted by Amir Fendi
Amir Fendi
Courses Plus Student 584 Points

Updating a Dictionary

Good day gents, when using an updateValue to update a value within a dictionary ... how to update more then one item within a single line ? can it be done ? or only one item per update ?

2 Answers

kjvswift93
kjvswift93
13,515 Points

The updateValue(_:forKey:) method only takes two parameters, one value and one key. So you cannot update more than one value in your dictionary using the updateValue method. I don't think any method exists that can be called on by a dictionary to update more than one of it's value's within a single method declaration.

David Papandrew
David Papandrew
8,386 Points
David Papandrew
David Papandrew
8,386 Points

Not sure about your exact use case, but updateValue method only lets you change one key/value pair at a time.

If you were applying the same change to all your dictionary values (e.g. making them all uppercase or appending a string), you could use a for-loop.

var myDict = [
    "SFO": "San Francisco",
    "LAX": "Los Angeles",
    "DFW": "Dallas Fort Worth"
]

for (key, value) in myDict {
    myDict.updateValue(value + " International Airport", forKey: key)
}
Amir Fendi
Amir Fendi
Courses Plus Student 584 Points

Thanks for answering ... but actually my question was if i can update more than one key/value at a time within a dictionary, not necessary making them upper case or lower case .... it's about changing the content of a specific key/value.