Removing a value at a specified index of a dictionary swift

Question

I am writing a function that deletes a search from an apps NSUserDefaults. The method removes the deleted search from the searches Dictionary. I am confused about the syntax of this function. I don't understand how we access the value of the searches Dictionary with the searches[tags[index]]. To access the value at that index of the searches Dictionary wouldn't we just say searches[index] ?

private var searches: Dictionary <String, String> = [:] // stores tag-query pairs
private var tags: Array<String> = [] // stores tags in user-specified order

        // returns the query String for the taga at a given index
        func queryForTagAtIndex(index: Int) -> String? {
            return searches[tags[index]]
        }

Martin R · Accepted Answer · 2015-02-20 07:44:58Z

Since your dictionary is of the type [String:String] to access or add a value to it, the key should be of type String and not Int. index is of Type Int. So it will give an error if we do return searches[index]. And since tags is of type String, we can use that as the key for the searches.

Here are some links that will help you : https://developer.apple.com/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/CollectionTypes.html

https://developer.apple.com/library/ios/documentation/General/Reference/SwiftStandardLibraryReference/Dictionary.html

And I would edit the code for readability purposes to this :

 private var searches:[String:String]=[String:String]() // stores tag-query pairs
 private var tags:[String] = [String]() // stores tags in user-specified order

// returns the query String for the taga at a given index
func queryForTagAtIndex(index: Int) -> String? {
   return searches[tags[index]]
}

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