Data Type Conversions in Swift

Before we start let’s see what is type conversion. Type Conversion is used to check the type of instances to find out whether it belongs to a particular class type or not using the type conversion method or approach. Basically, a Type Conversion is a method in which we can convert one instance data type to another instance data type by casting the variable or value within braces. For Example: var stringToFloatNum: Float = Float(67891)!

In Swift, one data type is converted into another data type by an XCode compiler at the compiler time. The type conversions can only be applied to compatible data types like integer, string, float, double,…etc. In this article, we will be learning about the type conversions in a Swift programming language with some same examples converting a string data type to an integer data type, integer data type to string data type, integer data type to float data type, float data type to integer data type, float data type to string data type and string data type to a float data type.

Syntax:

var <variable_name>: <data_type> = <conver_data_type>(<value>)

1. Example for Converting a Number to String Data Type

var intNumberToString: String = String(intNumberValue)

2. Example for Converting a String to Float Data Type

var stringToFloatNum: Float = Float(decimalstringValue)!

Note: In type conversion, the destination data type cannot be smaller than the source data type.

Here is a few examples where Data Types in Swift can be used for Type Conversions.

• To Integer Data Type Conversion >> Int(parameter) or Int(value)
• To Float Data Type Conversion >> Float(parameter) or Float(value)
• To String Data Type Conversion >> String(parameter)! or String(value)!

Convert Integer to String

This is a swift program where we are accepting a variable value as an Integer data type and converting that Integer variable value to a string data type and displaying the value and type using a print statement.

Swift

// Swift program to convert integer to string
import Swift

// Initializing variable and assigning
// an integer value to it.
var intNumber: Int = 789

// Initializing variable and Converting integer
// variable to string and assigning to it.
var intNumberToString: String = String(intNumber)

// Display output
print("Integer Value = \(intNumber) of type \(type(of: intNumber))")
print("String Value = \(intNumberToString) of type \(type(of:   intNumberToString))")

Output:

Integer Value = 789 of type Int
String Value = 789 of type String

Convert String to Integer

This is a swift program where we accept a variable value as a string data type and convert that string variable value to an integer data type and display the value and type using a print statement.

Swift

// Swift program to convert string to integer
import Swift

// Initializing variable and
// assigning string value to it.
var string: String = "789"

// Initializing variable and Converting
// string variable to integer and
// assigning to it.
var stringToInt: Int = Int(string)!

// Display the output
print("String Value = \(string) of type \(type(of: string))")
print("Integer Value = \(stringToInt) of type \(type(of: stringToInt))")

Output:

String Value = 789 of type String
Integer Value = 789 of type Int

Convert Integer to Float

This is a swift program where we are accepting a variable value as an integer data type and converting that integer variable value to a float data type and displaying the value and type using print statements.

Swift

// Swift program to convert integer to float
import Swift

// Initializing variable and assigning
// integer value to it.
var intNum: Int = 789

// Initializing variable and Converting integer
// variable to float and assigning to it
var intNumToFloat: Float = Float(intNum)

// Display the output
print("Integer Value = \(intNum) of type \(type(of: intNum))")
print("Float Value = \(intNumToFloat) of type \(type(of: intNumToFloat))")

Output:

Integer Value = 789 of type Int
Float Value = 789.0 of type Float

Convert Float to Integer

This is a swift program where we are accepting a variable value as a float data type and converting that float variable value to an Integer data type and displaying the value and type using a print statement.

Swift

// Swift program to convert float to integer
import Swift

// Initializing variable and
// assigning float value to it.
var floatNum: Float = 789.0089

// Initializing variable and Converting float
// variable to integer and assigning to it.
var floatNumToInt: Int = Int(floatNum)

// Display the output
print("Float Value = \(floatNum) of type \(type(of: floatNum))")

print("Integer Value = \(floatNumToInt) of type \(type(of: floatNumToInt))")

Output:

Float Value = 789.0089 of type Float
Integer Value = 789 of type Int

Convert String to Float

This is a swift program where we are accepting a variable value as a string data type and converting that string variable value to a float data type and displaying the value and type using a print statement.

Swift

// Swift program to convert String to Float
import Swift

// Initializing variable as string
// and assigning value to it.
var string : String = "789"

// Initializing variable and Converting string
// variable to float and assigning to it.
var stringToFloatNum: Float = Float(string)!

// Display the output
print("String Value = \(string) of type \(type(of: string)) ")
print("Float Value = \(stringToFloatNum) of type \(type(of: stringToFloatNum))")

Output:

String Value = 789 of type String  
Float Value = 789.0 of type Float