Question or problem with Swift language programming:
How could we convert anyobject to string in swift 3, it’s very easy in the older version by using.
var str = toString(AnyObject)
I tried String(AnyObject) but the output is always optional, even when i’m sure that AnyObject is not a optional value.
How to solve the problem:
Solution 1:
The compiler suggests that you replace your code with:
let s = String(describing: str)
One other option is available if you have a situation where you want to silently fail with an empty string rather than store something that might not originally be a string as a string.
let s = str as? String ?? ""
else you have the ways of identifying and throwing an error in the answers above/below.
Solution 2:
Here’s three options for you:
Option 1 – if let
if let b = a as? String { print(b) // Was a string } else { print("Error") // Was not a string }
Option 2 – guard let
guard let b = a as? String else { print("Error") // Was not a string return // needs a return or break here } print(b) // Was a string
Option 3 – let with ?? (null coalescing operator)
let b = a as? String ?? "" print(b) // Print a blank string if a was not a string
Solution 3:
Here’s a simple function (repl.it) that will mash any value into a string, with nil
becoming an empty string. I found it useful for dealing with JSON that inconsistently uses null
, blank, numbers, and numeric strings for IDs.
import Foundation func toString(_ value: Any?) -> String { return String(describing: value ?? "") } let d: NSDictionary = [ "i" : 42, "s" : "Hello, World!" ] dump(toString(d["i"])) dump(toString(d["s"])) dump(toString(d["x"]))
Prints:
- "42" - "Hello, World!" - ""
Solution 4:
Try
let a = "Test" as AnyObject guard let b = a as? String else { // Something went wrong handle it here } print(b) // Test
Solution 5:
try this –
var str:AnyObject? str = "Hello, playground" as AnyObject? if let value = str { var a = value as! String }
OR
var a = str as? String