say I have a variable
let stringArray = "[\"You\", \"Shall\", \"Not\", \"PASS!\"]"
// if I show this, it would look like this
print(stringArray)
["You", "Shall", "Not", "PASS!"]
now let's have an Array< String>
let array = ["You", "Shall", "Not", "PASS!"]
// if I convert this into string
// it would roughly be equal to the variable 'stringArray'
if String(array) == stringArray {
print("true")
} else {
print("false")
}
// output would be
true
now say what should I do to convert variable 'stringArray' to 'Array< String>'
The answer would be to convert the string using NSJSONSerialization
Thanks Vadian for that tip
let dataString = stringArray.dataUsingEncoding(NSUTF8StringEncoding)
let newArray = try! NSJSONSerialization.JSONObjectWithData(dataString!, options: []) as! Array<String>
for string in newArray {
print(string)
}
voila there you have it, it's now an array of strings
A small improvement for Swift 4.
Try this:
// Array of Strings
let array: [String] = ["red", "green", "blue"]
let arrayAsString: String = array.description
let stringAsData = arrayAsString.data(using: String.Encoding.utf16)
let arrayBack: [String] = try! JSONDecoder().decode([String].self, from: stringAsData!)
For other data types respectively:
// Set of Doubles
let set: Set<Double> = [1, 2.0, 3]
let setAsString: String = set.description
let setStringAsData = setAsString.data(using: String.Encoding.utf16)
let setBack: Set<Double> = try! JSONDecoder().decode(Set<Double>.self, from: setStringAsData!)
Related
I've an Dictionary which contains Array and that Array has another Dictionary ant it also has another array. How do I get the last array by using 'Dictionary.Filter'.
For Example
Dict1->Array1->Dict2->Array2.
Here I need
Array2
I want to get "DeviceLsit" Array
Check this out! Based on your screenshot, I have managed to achieve it!
func filterArray() {
let dictPlist = Dictionary<String, Any>()
if let arrKeyName = dictPlist["key"] as? Array<Dictionary<String, Any>> {
let yourSecondArray = arrKeyName.filter({ (keyDict) -> Bool in
guard let _ = keyDict["keyName"] as? Array<Any> else {
return false
}
return true
})
}
}
Hope this helps!
if you want array of DeviceLists you can got through categories and get device lists
let root: [String: Any] = ["Categories": [ ["deviceList": ["1","2","3","4"]], ["deviceList": ["5","6","7","8"]] ]]
if let categories = root["Categories"] as? [Any] {
var deviceLists: [String] = []
for cat in categories {
if let cat = cat as? [String: Any], let deviceNames = cat["deviceList"] as? [String] {
deviceLists.append(contentsOf: deviceNames)
}
}
print(deviceLists)
}
here is the short anser :
Assume that your desired Array has Any Type. you can make it as you want like String , Int etc...!
let dict = [String:[[String:[Any]]]]()
let arr = dict.flatMap({($0.value).flatMap({($0.values)})}).last
print(arr) <-- your desired Array
I am storing values from Json response like
self.NameArray = self.attachmentsArray.valueForKey("filename") as! NSArray
Output:
NameArray(("Din.pdf","img.jpeg"),(),(),("41_58"))
I got this output. I need to get the array only having ("Din.pdf","img.jpeg","41_58").
How to get it using swift code?
Convert NSArray to Swift Type [[String]]:
let NameArray:NSArray = [["Din.pdf","img.jpeg"], [], [], [ "41_58" ]]
let swiftArray = NameArray as! [[String]]
let flattenedArray = swiftArray.flatMap{ $0 }
Credits: Eric Aya and Flatten a Array of Arrays in Swift
If you do not want to convert it into Swift Type:
let NameArray:NSArray = [["Din.pdf","img.jpeg"], [], [], [ "41_58" ]]
let arrFiltered:NSMutableArray! = []
for arr in NameArray {
for a in arr as! NSArray {
arrFiltered.addObject(a)
}
}
print(arrFiltered)
I have [AnyObject] array
var updatedPos = [AnyObject]()
I am setting data in that according to my requirement like!
let para:NSMutableDictionary = NSMutableDictionary()
para.setValue(posId, forKey: "id")
para.setValue(posName, forKey: "job")
let jsonData = try! NSJSONSerialization.dataWithJSONObject(para, options: NSJSONWritingOptions())
let jsonString = NSString(data: jsonData, encoding: NSUTF8StringEncoding) as! String
self.updatedPos.append(jsonString)
Now in my code i have some requirement to remove the object from this array where id getting matched according to requirement Here is the code which i am trying to implement
for var i = 0; i < updatedPos.count; i++
{
let posItem = updatedPos[i]
print("Id=\(posItem)")
let pId = posItem["id"] as? String
print("secRId=\(pId)")
if removeId! == pId!
{
updatedPos.removeAtIndex(i)
}
}
Here print("Id=\(posItem)") give me output asId={"id":"51","job":"Programmer"} but here i am not able to access id from this object. here print("secRId=\(pId)") give me nil
First of all use native Swift collection types.
Second of all use types as specific as possible.
For example your [AnyObject] array can be also declared as an array of dictionaries [[String:AnyObject]]
var updatedPos = [[String:AnyObject]]()
Now create the dictionaries and add them to the array (in your example the dictionary is actually [String:String] but I keep the AnyObject values).
let para1 : [String:AnyObject] = ["id" : "51", "job" : "Programmer"]
let para2 : [String:AnyObject] = ["id" : "12", "job" : "Designer"]
updatedPos.append(para1)
updatedPos.append(para2)
If you want to remove an item by id use the filter function
let removeId = "12"
updatedPos = updatedPos.filter { $0["id"] as? String != removeId }
or alternatively
if let indexToDelete = updatedPos.indexOf{ $0["id"] as? String == removeId} {
updatedPos.removeAtIndex(indexToDelete)
}
The JSON serialization is not needed for the code you provided.
PS: Never write valueForKey: and setValue:forKey: unless you know exactly what it's doing.
After some little bit stuffs I have found the very easy and best solution for my question. And I want to do special thanks to #vadian. Because he teach me new thing here. Hey Thank you very much #vadian
Finally the answer is I had covert posItem in json Format for finding the id from Id={"id":"51","job":"Programmer"} this string
And the way is
let data = posItem.dataUsingEncoding(NSASCIIStringEncoding, allowLossyConversion: false)
do {
let json = try NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.MutableContainers)
if let dict = json as? [String: AnyObject] {
let id = dict["id"]
if removeId! == id! as! String
{
updatedLoc.removeAtIndex(i)
}
}
}
catch {
print(error)
}
[{"name":"Air Elemental","toughness":"4","printings":["LEA","BTD","7ED","8ED","9ED","10E","DD2","M10","DPA","ME4","DD3_JVC"]}]
I have a JSON where there is an array in each listing called "printings" as seen below, how would I take this array out of each listing and convert it into a string like "LEA-BTD-7ED". Here is what I have so far but its crashing.
let err : NSErrorPointer?
let dataPath = NSBundle.mainBundle().pathForResource("cardata", ofType: "json")
let data : NSData = try! NSData(contentsOfFile: dataPath! as String, options: NSDataReadingOptions.DataReadingMapped)
do{
var contents = try NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.AllowFragments) as! [AnyObject]
for var i = 0;i<contents.count;++i{
let printing = contents[i]["printings"] as! String
}
}
Here's the code:
let path = dataPath!
if let JSONData = NSData(contentsOfFile: path)
{
do
{
if let dictionariesArray = try NSJSONSerialization.JSONObjectWithData(JSONData, options: NSJSONReadingOptions()) as?
[[String: AnyObject]]
{
for dictionary in dictionariesArray
{
if let printingsArray = dictionary["printings"] as? [String]
{
let printingsString = printingsArray.joinWithSeparator("-")
print(printingsString)
}
}
}
}
catch
{
print("Could not parse file at \(path)")
}
}
Executing it prints "LEA-BTD-7ED-8ED-9ED-10E-DD2-M10-DPA-ME4-DD3_JVC"
You can't cast an Array (contents[i]["printings"]) to a String. What you want is Array's joinWithSeparator() method, like this:
let printing = contents[i]["printing"] as! Array
let printingStr = printing.joinWithSeparator("-")
(Actually, I'm not sure whether you need the as! Array; try it without it.)
I am trying to create an array of words from a string object retrieved from Parse. The object retrieved looks like this:
Then this line of code gives this.
let joinedWords = object["Words"] as! String
How do I convert joinedWords to an Array?
If you don't care about the order, you can use flatMap on the set:
var mySet = Set<String>()
for index in 1...5 {
mySet.insert("testwords\(index)")
}
let myArray = mySet.flatMap { $0 }
print(myArray) // "["testwords5", "testwords3", "testwords4", "testwords2", "testwords1"]"
If you want the list sorted alphabetically, you can make your array a var and use sortInPlace()
var myArray = mySet.flatMap { $0 }
myArray.sortInPlace()
print(myArray) // "["testwords1", "testwords2", "testwords3", "testwords4", "testwords5"]"
If object["Words"] is AnyObject, you will have to unwrap it.
if let joinedWordsSet = object["Words"] as? Set<String> {
var joinedWordsArray = joinedWordsSet.flatMap { $0 }
myArray.sortInPlace()
print(myArray)
}
Swift 3 note: sortInPlace() has been renamed sort().
Many thanks to #JAL for so much time on chat to solve this one. This is what we came up with. Its a bodge and no doubt there is a better way!
When uploading to Parse save the set as an array.
let wordsSet = (wordList?.words?.valueForKey("wordName"))! as! NSSet
let wordsArray = Array(wordsSet)
Then it saves to Parse - looking like a set, not an array or a dictionary.
let parseWordList = PFObject(className: "WordList")
parseWordList.setObject("\(wordsArray)", forKey: "Words")
parseWordList.saveInBackgroundWithBlock { (succeeded, error) -> Void in
if succeeded {
// Do something
} else {
print("Error: \(error) \(error?.userInfo)")
}
}
Then you can drop the [ ] off the string when its downloaded from Parse, and remove the , and add some "" and voila, there is an array that can be used e.g. to add to CoreData.
var joinedWords = object["Words"] as! String
joinedWords = String(joinedWords.characters.dropFirst())
joinedWords = String(joinedWords.characters.dropLast())
let joinedWordsArray = joinedWords.characters.split() {$0 == ","}.map{ String($0) } // Thanks #JAL!