how to convert null string to null swift

Question

I am new to Swift. I tried with this Swift link Detect a Null value in NSDictionaryNSDictionary, but I failed to do so.

Data:

"end_time" = "<null>"

Here is my code:

if endTime["end_time"] is NSNull {

    print("your session still available ")
 }
else{
   print("your session end \(endTime["end_time"])")
}

Every time it is going to else statement. May be I need to convert string to null or alternative solution. Could you help me please?

Thank you.

you can compare with the string `""` like so: `if endTime["end_time"] == ""` — Tomer Even, Dec 14 '16 at 08:05
what format is end_time when not "NSNull" (When It has a value) — Dylan, Dec 14 '16 at 08:33

Anni S · Answer 1 · 2016-12-15T13:44:10.143

-1

Here's how you check null in swift:

let time = endTime["end_time"]
if  time != "<null>" {
    print("time is not <null>")
}
else
{
    print("time is <null>")
}

edited Dec 15 '16 at 13:44

answered Dec 14 '16 at 07:59

Anni S

1,996
19
28

2

`` != `nil` – vadian Dec 14 '16 at 08:01
it leads to the same result, endTime["end_time"] equals "" it NOT nil. – Ahmad F Dec 14 '16 at 08:07

Mr. Bean · Answer 2 · 2017-01-02T07:56:37.027

You can create a NilCheck controller to check nil or null for various datatypes. For example i have created a function to remove null [if any] from the dictionary and store the array of dictionary in Userdefaults. Please be free to ask your queries :)

func removeNilAndSaveToLocalStore(array : [[String:Any]]) {

    var arrayToSave = [[String:Any]]()
    for place in array {

        var dict = [String:Any]()
        dict["AreaId"] =  NilCheck.sharedInstance.checkIntForNil(nbr: place["AreaId"]! as? Int)
        dict["AreaNameAr"] = NilCheck.sharedInstance.checkStringForNil(str: place["AreaNameAr"]! as? String)
        dict["AreaName"] = NilCheck.sharedInstance.checkStringForNil(str: place["AreaName"]! as? String)
        dict["GovernorateId"] = NilCheck.sharedInstance.checkIntForNil(nbr: place["GovernorateId"]! as? Int)
        arrayToSave.append(dict)
    }
    LocalStore.setAreaList(token: arrayToSave)
}

class NilCheck {

static let sharedInstance : NilCheck = {
    let instance = NilCheck()
    return instance
}()

func checkStringForNil(str : String?) -> String {

    guard let str = str else {
        return String() // return default string
    }
    return str
}
func checkIntForNil(nbr : Int?) -> Int {

    guard let num = nbr else {
        return 0 // return default Int
    }
    return num
} }

There is an operator that does what your fancy functions do `str ?? ""`, `num ?? 0`. — Sulthan, Jan 02 '17 at 07:59

how to convert null string to null swift

2 Answers2