DataItemExtractor Protocol Reference


                    
                    
                    getDataItem(key:)

Returns the DataItem at the given key, if it was there; otherwise nil.

Declaration

Swift

func getDataItem(key: String) -> DataItem?

Parameters

key

The key at which to look for the DataItem.

Return Value

A DataItem if one can be found for the given key.


                    
                    
                    get(key:as:)

Extension method

Returns the data at the given key in the requested type if the conversion is possible.

Supported types are:

Double
Float
Int
Int64
Bool
String
NSNumber

You can call this method without parameters if the return type can be inferred:

 let dataExtractor: DataItemExtractor = ...
 let anInt: Int? = dataExtractor.get(key: "someKey")

Alternatively the type must be specified as a parameter:

 let dataExtractor: DataItemExtractor = ...
 let anInt = dataExtractor.get(key: "someKey", as: Int.self)

Every numeric type (Int, Int64, Float, Double, NSNumber) can be used interchangeably and the conversion will be made following NSNumber conversion methods.

 let nsNumber = NSNumber(1.5)
 let dataExtractor: DataItemExtractor = DataObject(dictionary: ["someKey": nsNumber])
 let aDouble: Double? = dataExtractor.get(key: "someKey") // Double(1.5)
 let anInt: Int? = dataExtractor.get(key: "someKey") // Int(1)

Declaration

Swift

func get<T>(key: String, as type: T.Type = T.self) -> T? where T : DataInput

Parameters

`key`	The key at which to look for the item.
`type`	The expected type of the item.

Return Value

The value at the given key if it was found and if it was of the correct type.


                    
                    
                    getConvertible(key:converter:)

Extension method

Gets and converts the item at the given key using the given converter.

Declaration

Swift

func getConvertible<T>(key: String, converter: any DataItemConverter<T>) -> T?

Parameters

`key`	The key at which to look for the item.
`converter`	The converter used to convert the item to the expected type.

Return Value

The value at the given key after having been converted by the DataItemConverter.


                    
                    
                    getDataArray(key:)

Extension method

Returns the value as an Array of DataItems if the underlying value is an Array.

Warning

Do not cast the return object as any cast will likely fail. Use the appropriate methods to extract value from a DataItem.

Declaration

Swift

func getDataArray(key: String) -> [DataItem]?

Parameters

key

The key at which to look for the array.

Return Value

The array of DataItems, if an array is found at the given key.


                    
                    
                    getDataDictionary(key:)

Extension method

Returns the value as a Dictionary of DataItems if the underlying value is a Dictionary.

Warning

Do not cast the return object as any cast will likely fail. Use the appropriate methods to extract value from a DataItem.

Declaration

Swift

func getDataDictionary(key: String) -> [String : DataItem]?

Parameters

key

The key at which to look for the dictionary.

Return Value

The dictionary of DataItems, if a dictionary is found at the given key.


                    
                    
                    getArray(key:of:)

Extension method

Returns the value at the given key as an Array of the (optional) given type.

This method will follow the same principles of the get<T: DataInput>(key:as:) counterpart, but applies them on the individual Array elements.

Supported types are:

Double
Float
Int
Int64
Bool
String
NSNumber

You can call this method without parameters if the return type can be inferred:

 let dataExtractor: DataItemExtractor = ...
 let anIntArray: [Int?]? = dataExtractor.getArray(key: "someKey")

Alternatively the type must be specified as a parameter:

 let dataExtractor: DataItemExtractor = ...
 let anIntArray = dataExtractor.getArray(key: "someKey", of: Int.self)

Every numeric type (Int, Int64, Float, Double, NSNumber) can be used interchangeably and the conversion will be made following NSNumber conversion methods.

 let nsNumber = NSNumber(1.5)
 let dataExtractor: DataItemExtractor = DataObject(dictionary: ["someKey": [nsNumber]])
 let aDoubleArray = dataExtractor.getArray(key: "someKey", of: Double.self) // [Double(1.5)]
 let anIntArray = dataExtractor.getArray(key: "someKey", of: Int.self) // [Int(1)]

Declaration

Swift

func getArray<T>(key: String, of type: T.Type = T.self) -> [T?]? where T : DataInput

Parameters

`key`	The key at which to look for the array.
`type`	The expected type of each item of the array.

Return Value

The array of items of optional type at the given key if it was found. Each item will be nil if they were of the wrong type.


                    
                    
                    getDictionary(key:of:)

Extension method

Returns the value at the given key as an Dictionary of the (optional) given type.

This method will follow the same principles of the get<T: DataInput>(key:as:) counterpart, but applies them on the individual Dictionary elements.

Supported types are:

Double
Float
Int
Int64
Bool
String
NSNumber

You can call this method without parameters if the return type can be inferred:

 let dataExtractor: DataItemExtractor = ...
 let anIntDictionary: [String: Int?]? = dataExtractor.getDictionary(key: "someKey")

Alternatively the type must be specified as a parameter:

 let dataExtractor: DataItemExtractor = ...
 let anIntDictionary = dataExtractor.getDictionary(key: "someKey", of: Int.self)

Every numeric type (Int, Int64, Float, Double, NSNumber) can be used interchangeably and the conversion will be made following NSNumber conversion methods.

 let nsNumber = NSNumber(1.5)
 let dataExtractor: DataItemExtractor = DataObject(dictionary: ["someKey": nsNumber])
 let aDoubleDictionary = dataExtractor.getDictionary(key: "someKey", of: Double.self) // ["someKey": Double(1.5)]
 let anIntDictionary = dataExtractor.getDictionary(key: "someKey", of: Int.self) // ["someKey": Int(1)]

Declaration

Swift

func getDictionary<T>(key: String, of type: T.Type = T.self) -> [String : T?]? where T : DataInput

Parameters

`key`	The key at which to look for the dictionary.
`type`	The expected type of each item of the dictionary.

Return Value

The dictionary of items of optional type at the given key if it was found. Each item will be nil if they were of the wrong type.