Swift makes decoding JSON really easy. There’s no need to use a custom library for JSON parsing as the default API brings everything we need, from custom key mapping to formatting dates. If you like to improve your Swift knowledge, even more, check out the Swift category page. Two of the most popular posts on this blog are the Structure Of A SWIFT Message, Explained and the Difference between a SWIFT ACK and SWIFT NACK.Many of the readers of those posts have asked if i could do something similar detailing the SWIFT MT101 format. An MT103 is a standardised SWIFT payment message used specifically for cross border/international wire transfers. We use SWIFT for all payments made via Money Mover. MT103s are globally accepted as proofs of payment and include all payment details such as date, amount, currency, sender and recipient.
- Ios Swift Dateformatter
- Dateformatter Swiftui
- Swift Date Format Month Name
- Swift Convert Date To String
- Swift Date Formatter
- Swift Tutorial
- Swift Useful Resources
- Selected Reading
While doing programming in any programming language, you need to use different types of variables to store information. Variables are nothing but reserved memory locations to store values. This means that when you create a variable, you reserve some space in memory.
You may like to store information of various data types like string, character, wide character, integer, floating point, Boolean, etc. Based on the data type of a variable, the operating system allocates memory and decides what can be stored in the reserved memory.
Built-in Data Types
Swift 4 offers the programmer a rich assortment of built-in as well as user-defined data types. The following types of basic data types are most frequently when declaring variables −
- Int or UInt − This is used for whole numbers. More specifically, you can use Int32, Int64 to define 32 or 64 bit signed integer, whereas UInt32 or UInt64 to define 32 or 64 bit unsigned integer variables. For example, 42 and -23.
- Float Movavi photo editor 5 2 1 – image editor photoshop. − This is used to represent a 32-bit floating-point number and numbers with smaller decimal points. For example, 3.14159, 0.1, and -273.158.
- Double − This is used to represent a 64-bit floating-point number and used when floating-point values must be very large. For example, 3.14159, 0.1, and -273.158.
- Bool − This represents a Boolean value which is either true or false.
- String − This is an ordered collection of characters. For example, 'Hello, World!'
- Character − This is a single-character string literal. For example, 'C'
- Optional − This represents a variable that can hold either a value or no value.
- Tuples − This is used to group multiple values in single Compound Value.
We have listed here a few important points related to Integer types −
- On a 32-bit platform, Int is the same size as Int32.
- On a 64-bit platform, Int is the same size as Int64.
- On a 32-bit platform, UInt is the same size as UInt32.
- On a 64-bit platform, UInt is the same size as UInt64. Snapndrag pro 4 4 hp.
- Int8, Int16, Int32, Int64 can be used to represent 8 Bit, 16 Bit, 32 Bit, and 64 Bit forms of signed integer.
- UInt8, UInt16, UInt32, and UInt64 can be used to represent 8 Bit, 16 Bit, 32 Bit and 64 Bit forms of unsigned integer.
Bound Values
The following table shows the variable type, how much memory it takes to store the value in memory, and what is the maximum and minimum value which can be stored in such type of variables.
Type | Typical Bit Width | Typical Range |
---|---|---|
Int8 | 1byte | -127 to 127 |
UInt8 | 1byte | 0 to 255 |
Int32 | 4bytes | -2147483648 to 2147483647 |
UInt32 | 4bytes | 0 to 4294967295 |
Int64 | 8bytes | -9223372036854775808 to 9223372036854775807 |
UInt64 | 8bytes | 0 to 18446744073709551615 |
Float | 4bytes | 1.2E-38 to 3.4E+38 (~6 digits) |
Double | 8bytes | 2.3E-308 to 1.7E+308 (~15 digits) |
Type Aliases
You can create a new name for an existing type using typealias. Here is the simple syntax to define a new type using typealias −
For example, the following line instructs the compiler that Feet is another name for Int −
Now, the following declaration is perfectly legal and creates an integer variable called distance −
When we run the above program using playground, we get the following result.
Type Safety
Swift 4 is a type-safe language which means if a part of your code expects a String, you can't pass it an Int by mistake.
As Swift 4 is type-safe, it performs type-checks when compiling your code and flags any mismatched types as errors.
When we compile the above program, it produces the following compile time error.
Type Inference
Type inference enables a compiler to deduce the type of a particular expression automatically when it compiles your code, simply by examining the values you provide. Swift 4 uses type inference to work out the appropriate type as follows.
When we run the above program using playground, we get the following result −
Working with dates in iOS10 can be a bit confusing. There are several different types associated with dates. You can use them for telling time, scheduling time and setting the differences between two times. In this lesson, let’s look at the different types of dates. I’ll use a playground to do this. You can download here the full lesson as a zip file if you wish, or just type along. The file has the entire lesson, so if you load it on iPad Playgrounds, it will format like this post.
The simplest date representation is from the type
Date
. For the current date, instantiate a variable with the constructor like this:Ios Swift Dateformatter
Prints
2016-11-10 11:58:36 +0000
to the console.Time Intervals
On the other hand, you might want a measure of time. For this, use the type
TimeInterval
. This is a measure of time using seconds. They are of Double
type. I’ll set a few constants using time intervals for day, hour and minute.You can set a date based on the time interval. If you want a time interval different from now, use the constructor
Date(timeIntervalSinceNow:)
Gives you a date one minute from now
2016-11-10 11:59:36 +0000
. If you want a date where you add or subtract a time interval, use Date(timeInterval:since:)
Gives us a date an hour from now:
2016-11-10 12:59:36 +0000
.The date looks ugly. Let’s make the date look better with a date formatter. Start with initializing a date formatter
Date formatters need you to set a style for the date using the
dateStyle
property and time property timeStyle
. You have a choice of .full
.long
, .medium
, .short
, and .none
There’s a function on date formatters,
string(from:)
that returns a string with the formatted date.You’ll get a full date like
Thursday, November 10, 2016 at 6:59:36 AM Central Standard Time
. Change the styles to .short
You’ll find printed something like
11/10/16, 7:20 AM
on the console. If you want only a date or a time, use .none
Prints just the time
Date formatters are locale dependent. They use the current locale by default. You can change the locale and use that locale’s format. For example If I want the time for some where with really authentic pizza,
7:20:53 AM
Date formatters are locale dependent. They use the current locale by default. You can change the locale and use that locale’s format. For example If I want the time for some where with really authentic pizza,
Prints to the console the Italian date format
10 nov 2016, 06:59:36
This is good for relative dates from a time frame. What if you want an absolute date? That’s where
DateComponents
comes into play. A date component provides a way to add components for a date. Initialize DateComponents
like this:You assign to date componenets the date
Date components are optional values. When a value is not set it returns
nil
. If you have a nil
value for one component, operations on the dateComponents
object will cause an nil
error. There is a property isValidDate
to confirm if you have all the information.Prints
false
. You don’t have enough components yet. Include the calendar used in a date componenets object. Usually this is the current calendar for the system. A calendar fills in the rest of the information the date componenets needs to make a valid date. You can get the current calendar using Calendar.current
The console prints
true.
The date components have a property date
if you need a value of type Date
. Of course you can format this way, changing the components back into dates.Prints
You can also convert a date to date components. However, you do it from the current calendar, not the
04 nov 2016, 13:08:00
You can also convert a date to date components. However, you do it from the current calendar, not the
Date
type. Make a set of Calendar
components. For most cases, include the component .calendar
to avoid a nil
in the components.Dateformatter Swiftui
Using the current calendar, get the components
Print the date using the date formatter.
Swift Date Format Month Name
Prints the date
Date components can be changed. The date components are all optional type
10 nov 2016, 06:19:53
.Date components can be changed. The date components are all optional type
Int
. While it is easier to change them using Date
and TimeInterval
, you might need to do it this way if you’ve created a series of controls in your UI to set a date. For example, to add five days do this:The console prints
Each of these types have their purposes.
15 nov 2016, 06:19:53
.Each of these types have their purposes.
Date
is the simplest and best for the current date and dates based on the current date. To show an interval in seconds, use the TimeInterval
. To work with indivdual date components, use DateComponents
. You’ll find each of these in other API’s as well. For example, all three have purposes in the UserNotification
framework as event triggers. Learing how to use all three will help you display time and schedule time throughout iOS.Swift Convert Date To String
The Whole code
Swift Date Formatter
You can download here the full lesson as a zip file.