IOS8 development of Swift-self-study road (third day)

String type

Countelements () calculates the string length.

Compare strings equal, = =.

The string is empty. IsEmpty

The string is converted to int. ToInt ()

Optional type

Int?

!

Nil

Array type

Shoppinglist.insert ("abc", atindex:0)

Shoppinglist.append ("abc", "BAC")

Shoppinglist.removeatindex (0)//return Delete value

shoppinglist.count//Array length

For item in Shoppinglist {

println (item)

}

For (index, value) in enumerate (shoppinglist) {

....

}

Dictionary type

airports["LHR"] = "London"

Airports.removevalueforkey ()

Airports.count

For (Airportcode, airportname) in airports{

}

For (Airportcode in Airports.keys {

}

For (Airportname in airports.values {

}

Let Airportcodes = Array (Airports.keys)

IOS8 development of Swift-self-study road (third day)