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I've a string with minutes and seconds in format "minutes:seconds". For example, "5:36". I want to convert it to Int value. For example "5:36" string should be 336 Int value. How this can be done?
let timeString = "5:36"
let timeStringArray = timeString.split(separator: ":")
let minutesInt = Int(timeStringArray[0]) ?? 0
let secondsInt = Int(timeStringArray[1]) ?? 0
let resultInt = minutesInt * 60 + secondsInt
print(resultInt)
Here's a simple extension you can use which will validate the format of your input string too:
import Foundation
extension String {
func toSeconds() -> Int? {
let elements = components(separatedBy: ":")
guard elements.count == 2 else {
print("Provided string doesn't have two sides separated by a ':'")
return nil
}
guard let minutes = Int(elements[0]),
let seconds = Int(elements[1]) else {
print("Either the minute value or the seconds value cannot be converted to an Int")
return nil
}
return (minutes*60) + seconds
}
}
Usage:
let testString1 = "5:36"
let testString2 = "35:36"
print(testString1.toSeconds()) // prints: "Optional(336)"
print(testString2.toSeconds()) // prints: "Optional(2136)"
I tried out your example on the playground here's the code:
import Foundation
let time1String = "0:00"
let time2String = "5:36"
let timeformatter = DateFormatter()
timeformatter.dateFormat = "m:ss"
let time1 = timeformatter.date(from: time1String)
let time2 = timeformatter.date(from: time2String)
if let time1 = time1 {
print(time2?.timeIntervalSince(time1)) // prints: Optional(336.0)
}
I'm trying to work out how to cast an Int into a String in Swift.
I figure out a workaround, using NSNumber but I'd love to figure out how to do it all in Swift.
let x : Int = 45
let xNSNumber = x as NSNumber
let xString : String = xNSNumber.stringValue
Converting Int to String:
let x : Int = 42
var myString = String(x)
And the other way around - converting String to Int:
let myString : String = "42"
let x: Int? = myString.toInt()
if (x != nil) {
// Successfully converted String to Int
}
Or if you're using Swift 2 or 3:
let x: Int? = Int(myString)
Check the Below Answer:
let x : Int = 45
var stringValue = "\(x)"
print(stringValue)
Here are 4 methods:
var x = 34
var s = String(x)
var ss = "\(x)"
var sss = toString(x)
var ssss = x.description
I can imagine that some people will have an issue with ss. But if you were looking to build a string containing other content then why not.
In Swift 3.0:
var value: Int = 10
var string = String(describing: value)
Swift 4:
let x:Int = 45
let str:String = String(describing: x)
Developer.Apple.com > String > init(describing:)
The String(describing:) initializer is the preferred way to convert an instance of any type to a string.
Custom String Convertible
Just for completeness, you can also use:
let x = 10.description
or any other value that supports a description.
Swift 4:
Trying to show the value in label without Optional() word.
here x is a Int value using.
let str:String = String(x ?? 0)
To save yourself time and hassle in the future you can make an Int extension. Typically I create a shared code file where I put extensions, enums, and other fun stuff. Here is what the extension code looks like:
extension Int
{
func toString() -> String
{
var myString = String(self)
return myString
}
}
Then later when you want to convert an int to a string you can just do something like:
var myNumber = 0
var myNumberAsString = myNumber.toString()
in swift 3.0 this is how we can convert Int to String and String to Int
//convert Integer to String in Swift 3.0
let theIntegerValue :Int = 123 // this can be var also
let theStringValue :String = String(theIntegerValue)
//convert String to Integere in Swift 3.0
let stringValue : String = "123"
let integerValue : Int = Int(stringValue)!
for whatever reason the accepted answer did not work for me. I went with this approach:
var myInt:Int = 10
var myString:String = toString(myInt)
Multiple ways to do this :
var str1:String="\(23)"
var str2:String=String(format:"%d",234)
let intAsString = 45.description // "45"
let stringAsInt = Int("45") // 45
Swift 2:
var num1 = 4
var numString = "56"
var sum2 = String(num1) + numString
var sum3 = Int(numString)
Swift String performance
A little bit about performance
UI Testing Bundle on iPhone 7(real device) with iOS 14
let i = 0
lt result1 = String(i) //0.56s 5890kB
lt result2 = "\(i)" //0.624s 5900kB
lt result3 = i.description //0.758s 5890kB
import XCTest
class ConvertIntToStringTests: XCTestCase {
let count = 1_000_000
func measureFunction(_ block: () -> Void) {
let metrics: [XCTMetric] = [
XCTClockMetric(),
XCTMemoryMetric()
]
let measureOptions = XCTMeasureOptions.default
measureOptions.iterationCount = 5
measure(metrics: metrics, options: measureOptions) {
block()
}
}
func testIntToStringConstructor() {
var result = ""
measureFunction {
for i in 0...count {
result += String(i)
}
}
}
func testIntToStringInterpolation() {
var result = ""
measureFunction {
for i in 0...count {
result += "\(i)"
}
}
}
func testIntToStringDescription() {
var result = ""
measureFunction {
for i in 0...count {
result += i.description
}
}
}
}
iam using this simple approach
String to Int:
var a = Int()
var string1 = String("1")
a = string1.toInt()
and from Int to String:
var a = Int()
a = 1
var string1 = String()
string1= "\(a)"
Convert Unicode Int to String
For those who want to convert an Int to a Unicode string, you can do the following:
let myInteger: Int = 97
// convert Int to a valid UnicodeScalar
guard let myUnicodeScalar = UnicodeScalar(myInteger) else {
return ""
}
// convert UnicodeScalar to String
let myString = String(myUnicodeScalar)
// results
print(myString) // a
Or alternatively:
let myInteger: Int = 97
if let myUnicodeScalar = UnicodeScalar(myInteger) {
let myString = String(myUnicodeScalar)
}
I prefer using String Interpolation
let x = 45
let string = "\(x)"
Each object has some string representation. This makes things simpler. For example if you need to create some String with multiple values. You can also do any math in it or use some conditions
let text = "\(count) \(count > 1 ? "items" : "item") in the cart. Sum: $\(sum + shippingPrice)"
exampleLabel.text = String(yourInt)
To convert String into Int
var numberA = Int("10")
Print(numberA) // It will print 10
To covert Int into String
var numberA = 10
1st way)
print("numberA is \(numberA)") // It will print 10
2nd way)
var strSomeNumber = String(numberA)
or
var strSomeNumber = "\(numberA)"
let a =123456888
var str = String(a)
OR
var str = a as! String
In swift 3.0, you may change integer to string as given below
let a:String = String(stringInterpolationSegment: 15)
Another way is
let number: Int = 15
let _numberInStringFormate: String = String(number)
//or any integer number in place of 15
If you like swift extension, you can add following code
extension Int
{
var string:String {
get {
return String(self)
}
}
}
then, you can get string by the method you just added
var x = 1234
var s = x.string
let Str = "12"
let num: Int = 0
num = Int (str)
I have a function below which I use to format a string. The string is something like this "PT1H3M20S" which means 1 hour 3 minutes and 20 seconds. In my function, I want to format the string to 1:03:20 and it works fine but sometimes, I get the string like this "PT1H20S" which means 1 hour and 20 seconds and my function format it like this 1:20 which makes people read it as 1 minute and 20 seconds. Any suggestions?
func formatDuration(videoDuration: String) -> String{
let formattedDuration = videoDuration.replacingOccurrences(of: "PT", with: "").replacingOccurrences(of: "H", with:":").replacingOccurrences(of: "M", with: ":").replacingOccurrences(of: "S", with: "")
let components = formattedDuration.components(separatedBy: ":")
var duration = ""
for component in components {
duration = duration.count > 0 ? duration + ":" : duration
if component.count < 2 {
duration += "0" + component
continue
}
duration += component
}
// instead of 01:10:10, display 1:10:10
if duration.first == "0"{
duration.remove(at: duration.startIndex)
}
return duration
}
Call it:
print(formatDuration(videoDuration: "PT1H15S")
You can also just search the indexes of your hours, minutes and seconds and use DateComponentsFormatter positional style to format your video duration:
Create a static positional date components formatter:
extension Formatter {
static let positional: DateComponentsFormatter = {
let formatter = DateComponentsFormatter()
formatter.unitsStyle = .positional
return formatter
}()
}
And your format duration method:
func formatVideo(duration: String) -> String {
var duration = duration
if duration.hasPrefix("PT") { duration.removeFirst(2) }
let hour, minute, second: Double
if let index = duration.firstIndex(of: "H") {
hour = Double(duration[..<index]) ?? 0
duration.removeSubrange(...index)
} else { hour = 0 }
if let index = duration.firstIndex(of: "M") {
minute = Double(duration[..<index]) ?? 0
duration.removeSubrange(...index)
} else { minute = 0 }
if let index = duration.firstIndex(of: "S") {
second = Double(duration[..<index]) ?? 0
} else { second = 0 }
return Formatter.positional.string(from: hour * 3600 + minute * 60 + second) ?? "0:00"
}
let duration = "PT1H3M20S"
formatVideo(duration: duration) // "1:03:20"
Since you need to see what unit is after each number, you can't start by removing the units from the string.
Here is a solution that uses Scanner to parse the original string and finds the number of hours, minutes, and seconds to build the final result.
This also changes the return value to be optional to indicate that the passed in string isn't valid.
func formatDuration(videoDuration: String) -> String? {
let scanner = Scanner(string: videoDuration)
if scanner.scanString("PT", into: nil) {
var hours = 0
var mins = 0
var secs = 0
let units = CharacterSet(charactersIn: "HMS")
while !scanner.isAtEnd {
var num = 0
if scanner.scanInt(&num) {
var unit: NSString?
if scanner.scanCharacters(from: units, into: &unit) {
switch unit! {
case "H":
hours = num
case "M":
mins = num
case "S":
secs = num
default:
return nil // Invalid unit
}
} else {
return nil // No unit after the number
}
} else {
return nil // No integer
}
}
if hours > 0 {
return String(format: "%d:%02d:%02d", hours, mins, secs)
} else {
return String(format: "%02d:%02d", mins, secs)
}
} else {
return nil // No leading PT
}
}
print(formatDuration(videoDuration: "PT1H3M20S") ?? "bad")
print(formatDuration(videoDuration: "PT1H15S") ?? "bad")
print(formatDuration(videoDuration: "PT4M6") ?? "bad")
Output:
1:03:20
1:00:15
bad
In your case, your string carries no character for minutes, so you can make a check if the string does not contain minutes, then add "00:" between 1:20 and format appropriately.
This question already has answers here:
Leading zeros for Int in Swift
(12 answers)
Closed 6 years ago.
i've some issue to found a proper solution in swift3 to do this :
I have a date like 10h20m. When my hours are under 10 it will be "5h30". I want to out "05h30".
class func getTime(_ user: SUser) -> String {
let currentDate = Date()
let firstDate = user.firstDate
let difference = firstDate?.timeIntervalSince(now)
let hours = String(Int(difference!) / 3600)
let minutes = String(Int(difference!) / 60 % 60)
let time = "\(hours)h\(minutes)m"
return time
}
if someone have an idea how do that simply et properly thank you !
You can do something like this
class func getTime(_ user: SUser) -> String {
let currentDate = Date()
let firstDate = user.firstDate
let difference = firstDate?.timeIntervalSince(now)
let hours = String(Int(difference!) / 3600)
if Int(hours)! < 10 {
hours = "0\(hours)"
}
var minutes = String(Int(difference!) / 60 % 60)
if Int(minutes)! < 10 {
minutes = "0\(minutes)"
}
let time = "\(hours)h\(minutes)m"
return time
}
or a better way
class func getTime(_ user: SUser) -> String {
let currentDate = Date()
let firstDate = user.firstDate
let difference = firstDate?.timeIntervalSince(now)
let hours = Int(difference!) / 3600
let minutes = Int(difference!) / 60 % 60
let time = "\(String(format: "%02d", hours))h\(String(format: "%02d", minutes))m"
return time
}
Suggested here - Leading zeros for Int in Swift
class func getTime(_ user: SUser) -> String {
let currentDate = Date()
let firstDate = user.firstDate
let difference = firstDate?.timeIntervalSince(now)
var hours = String(Int(difference!) / 3600)
if ((Int(difference!) / 3600)<10) {
hours = "0\(hours)"
}
var minutes = String(Int(difference!) / 60 % 60)
if ((Int(difference!) / 60 % 60)<10) {
minutes = "0\(minutes)"
}
let time = "\(hours)h\(minutes)m"
return time
}
I think you would be better off with a simple formatting function that you can call inline.
Try something like
func formatHour(hour:Int) -> String {
return (String(hour).characters.count == 1) ? "0\(hour)" : "\(hour)"
}
let hour = 5
print("\(formatHour(hour: hour))") // output "05"
You can adjust this as needed, maybe pass the string in instead and save doing the conversion in the function. could also add a guard statement to ensure that the number is within the bounds of hours, or a string is less than three characters etc.
I need to create a String with format which can convert Int, Int64, Double, etc types into String. Using Objective-C, I can do it by:
NSString *str = [NSString stringWithFormat:#"%d , %f, %ld, %#", INT_VALUE, FLOAT_VALUE, DOUBLE_VALUE, STRING_VALUE];
How to do same but in Swift?
I think this could help you:
import Foundation
let timeNow = time(nil)
let aStr = String(format: "%#%x", "timeNow in hex: ", timeNow)
print(aStr)
Example result:
timeNow in hex: 5cdc9c8d
nothing special
let str = NSString(format:"%d , %f, %ld, %#", INT_VALUE, FLOAT_VALUE, LONG_VALUE, STRING_VALUE)
let str = "\(INT_VALUE), \(FLOAT_VALUE), \(DOUBLE_VALUE), \(STRING_VALUE)"
Update: I wrote this answer before Swift had String(format:) added to it's API. Use the method given by the top answer.
No NSString required!
String(format: "Value: %3.2f\tResult: %3.2f", arguments: [2.7, 99.8])
or
String(format:"Value: %3.2f\tResult: %3.2f", 2.7, 99.8)
I would argue that both
let str = String(format:"%d, %f, %ld", INT_VALUE, FLOAT_VALUE, DOUBLE_VALUE)
and
let str = "\(INT_VALUE), \(FLOAT_VALUE), \(DOUBLE_VALUE)"
are both acceptable since the user asked about formatting and both cases fit what they are asking for:
I need to create a string with format which can convert int, long, double etc. types into string.
Obviously the former allows finer control over the formatting than the latter, but that does not mean the latter is not an acceptable answer.
First read Official documentation for Swift language.
Answer should be
var str = "\(INT_VALUE) , \(FLOAT_VALUE) , \(DOUBLE_VALUE), \(STRING_VALUE)"
println(str)
Here
1) Any floating point value by default double
EX.
var myVal = 5.2 // its double by default;
-> If you want to display floating point value then you need to explicitly define such like a
EX.
var myVal:Float = 5.2 // now its float value;
This is far more clear.
let INT_VALUE=80
let FLOAT_VALUE:Double= 80.9999
let doubleValue=65.0
let DOUBLE_VALUE:Double= 65.56
let STRING_VALUE="Hello"
let str = NSString(format:"%d , %f, %ld, %#", INT_VALUE, FLOAT_VALUE, DOUBLE_VALUE, STRING_VALUE);
println(str);
The accepted answer is definitely the best general solution for this (i.e., just use the String(format:_:) method from Foundation) but...
If you are running Swift ≥ 5, you can leverage the new StringInterpolationProtocol protocol to give yourself some very nice syntax sugar for common string formatting use cases in your app.
Here is how the official documentation summarizes this new protocol:
Represents the contents of a string literal with interpolations while it’s being built up.
Some quick examples:
extension String.StringInterpolation {
/// Quick formatting for *floating point* values.
mutating func appendInterpolation(float: Double, decimals: UInt = 2) {
let floatDescription = String(format: "%.\(decimals)f%", float)
appendLiteral(floatDescription)
}
/// Quick formatting for *hexadecimal* values.
mutating func appendInterpolation(hex: Int) {
let hexDescription = String(format: "0x%X", hex)
appendLiteral(hexDescription)
}
/// Quick formatting for *percents*.
mutating func appendInterpolation(percent: Double, decimals: UInt = 2) {
let percentDescription = String(format: "%.\(decimals)f%%", percent * 100)
appendLiteral(percentDescription)
}
/// Formats the *elapsed time* since the specified start time.
mutating func appendInterpolation(timeSince startTime: TimeInterval, decimals: UInt = 2) {
let elapsedTime = CACurrentMediaTime() - startTime
let elapsedTimeDescription = String(format: "%.\(decimals)fs", elapsedTime)
appendLiteral(elapsedTimeDescription)
}
}
which could be used as:
let number = 1.2345
"Float: \(float: number)" // "Float: 1.23"
"Float: \(float: number, decimals: 1)" // "Float: 1.2"
let integer = 255
"Hex: \(hex: integer)" // "Hex: 0xFF"
let rate = 0.15
"Percent: \(percent: rate)" // "Percent: 15.00%"
"Percent: \(percent: rate, decimals: 0)" // "Percent: 15%"
let startTime = CACurrentMediaTime()
Thread.sleep(forTimeInterval: 2.8)
"∆t was \(timeSince: startTime)" // "∆t was 2.80s"
"∆t was \(timeSince: startTime, decimals: 0)" // "∆t was 3s"
This was introduced by SE-0228, so please be sure to read the original proposal for a deeper understanding of this new feature. Finally, the protocol documentation is helpful as well.
I know a lot's of time has passed since this publish, but I've fallen in a similar situation and create a simples class to simplify my life.
public struct StringMaskFormatter {
public var pattern : String = ""
public var replecementChar : Character = "*"
public var allowNumbers : Bool = true
public var allowText : Bool = false
public init(pattern:String, replecementChar:Character="*", allowNumbers:Bool=true, allowText:Bool=true)
{
self.pattern = pattern
self.replecementChar = replecementChar
self.allowNumbers = allowNumbers
self.allowText = allowText
}
private func prepareString(string:String) -> String {
var charSet : NSCharacterSet!
if allowText && allowNumbers {
charSet = NSCharacterSet.alphanumericCharacterSet().invertedSet
}
else if allowText {
charSet = NSCharacterSet.letterCharacterSet().invertedSet
}
else if allowNumbers {
charSet = NSCharacterSet.decimalDigitCharacterSet().invertedSet
}
let result = string.componentsSeparatedByCharactersInSet(charSet)
return result.joinWithSeparator("")
}
public func createFormattedStringFrom(text:String) -> String
{
var resultString = ""
if text.characters.count > 0 && pattern.characters.count > 0
{
var finalText = ""
var stop = false
let tempString = prepareString(text)
var formatIndex = pattern.startIndex
var tempIndex = tempString.startIndex
while !stop
{
let formattingPatternRange = formatIndex ..< formatIndex.advancedBy(1)
if pattern.substringWithRange(formattingPatternRange) != String(replecementChar) {
finalText = finalText.stringByAppendingString(pattern.substringWithRange(formattingPatternRange))
}
else if tempString.characters.count > 0 {
let pureStringRange = tempIndex ..< tempIndex.advancedBy(1)
finalText = finalText.stringByAppendingString(tempString.substringWithRange(pureStringRange))
tempIndex = tempIndex.advancedBy(1)
}
formatIndex = formatIndex.advancedBy(1)
if formatIndex >= pattern.endIndex || tempIndex >= tempString.endIndex {
stop = true
}
resultString = finalText
}
}
return resultString
}
}
The follow link send to the complete source code:
https://gist.github.com/dedeexe/d9a43894081317e7c418b96d1d081b25
This solution was base on this article:
http://vojtastavik.com/2015/03/29/real-time-formatting-in-uitextfield-swift-basics/
There is a simple solution I learned with "We <3 Swift" if you can't either import Foundation, use round() and/or does not want a String:
var number = 31.726354765
var intNumber = Int(number * 1000.0)
var roundedNumber = Double(intNumber) / 1000.0
result: 31.726
Use this following code:
let intVal=56
let floatval:Double=56.897898
let doubleValue=89.0
let explicitDaouble:Double=89.56
let stringValue:"Hello"
let stringValue="String:\(stringValue) Integer:\(intVal) Float:\(floatval) Double:\(doubleValue) ExplicitDouble:\(explicitDaouble) "
The beauty of String(format:) is that you can save a formatting string and then reuse it later in dozen of places. It also can be localized in this single place. Where as in case of the interpolation approach you must write it again and again.
Simple functionality is not included in Swift, expected because it's included in other languages, can often be quickly coded for reuse. Pro tip for programmers to create a bag of tricks file that contains all this reuse code.
So from my bag of tricks we first need string multiplication for use in indentation.
#inlinable func * (string: String, scalar: Int) -> String {
let array = [String](repeating: string, count: scalar)
return array.joined(separator: "")
}
and then the code to add commas.
extension Int {
#inlinable var withCommas:String {
var i = self
var retValue:[String] = []
while i >= 1000 {
retValue.append(String(format:"%03d",i%1000))
i /= 1000
}
retValue.append("\(i)")
return retValue.reversed().joined(separator: ",")
}
#inlinable func withCommas(_ count:Int = 0) -> String {
let retValue = self.withCommas
let indentation = count - retValue.count
let indent:String = indentation >= 0 ? " " * indentation : ""
return indent + retValue
}
}
I just wrote this last function so I could get the columns to line up.
The #inlinable is great because it takes small functions and reduces their functionality so they run faster.
You can use either the variable version or, to get a fixed column, use the function version. Lengths set less than the needed columns will just expand the field.
Now you have something that is pure Swift and does not rely on some old objective C routine for NSString.
Since String(format: "%s" ...) is crashing at run time, here is code to allow write something like "hello".center(42); "world".alignLeft(42):
extension String {
// note: symbol names match to nim std/strutils lib:
func align (_ boxsz: UInt) -> String {
self.withCString { String(format: "%\(boxsz)s", $0) }
}
func alignLeft (_ boxsz: UInt) -> String {
self.withCString { String(format: "%-\(boxsz)s", $0) }
}
func center (_ boxsz: UInt) -> String {
let n = self.count
guard boxsz > n else { return self }
let padding = boxsz - UInt(n)
let R = padding / 2
guard R > 0 else { return " " + self }
let L = (padding%2 == 0) ? R : (R+1)
return " ".withCString { String(format: "%\(L)s\(self)%\(R)s", $0,$0) }
}
}
Success to try it:
var letters:NSString = "abcdefghijkl"
var strRendom = NSMutableString.stringWithCapacity(strlength)
for var i=0; i<strlength; i++ {
let rndString = Int(arc4random() % 12)
//let strlk = NSString(format: <#NSString#>, <#CVarArg[]#>)
let strlk = NSString(format: "%c", letters.characterAtIndex(rndString))
strRendom.appendString(String(strlk))
}