ios - check for nil and extract data from dictionary in swift -

if user provides date value store in dictionary:

let dict:dictionary<string, any> = ["fromdate":fromdate any] 

if user not provide date value store in dictionary this:

let dict:dictionary<string, any> = ["fromdate": [:] ] 

i tried retrieve value dictionary inside cellforrowat function this:

let dict:dictionary<string, any> = alldates[indexpath.row] guard let fromdate:string = getdatestring(createddate: dict["fromdate"] as! date) != nil else {         fromdate:string = "none" } cell.fromdatelabel.text = gettimestringiso8601(createddate: fromdate) 

this date string function

func getdatestring(createddate:date) -> string{     let formatter = dateformatter()     formatter.calendar = calendar(identifier: .iso8601)     formatter.locale = locale(identifier: "en_us_posix")     formatter.locale = locale.current     formatter.timezone = timezone(secondsfromgmt: 0)     formatter.dateformat = "yyyy-mm-dd"     return formatter.string(from: createddate) } 

i error on guard statement:

type ‘string’ not optional value can never nil

how can check if date not nil , date converted , if date nil skip , put in statement “none” instead of date?

the error in guard statement because method getdatestring: not returns optional value. checking return value of method never nil per definition. need check date value dict optional.

try like,

var fromdate = "none"  if let dateval = dict["fromdate"] as? date {     fromdate = getdatestring(createddate: dateval)     cell.fromdatelabel.text = gettimestringiso8601(createddate: fromdate) } else {     cell.fromdatelabel.text = fromdate }