will xcode parse an empty string to a double? code example
Example: string to double swift
let lessPrecisePI = Float("3.14")
let morePrecisePI = Double("3.1415926536")
let invalidNumber = Float("alphabet")
if let cost = Double(textField.text!) {
print("The user entered a value price of \(cost)")
} else {
print("Not a valid number: \(textField.text!)")
}
let formatter = NumberFormatter()
formatter.locale = Locale.current
formatter.numberStyle = .decimal
let number = formatter.number(from: "9,999.99")