Swift Developer Question: Download Questions PDF
Explain me what Is The Significance Of “?” In Swift?
Answer:
The question mark (?) is used during the declaration of a property. If the property does not hold a value, the question mark (?) helps to avoiding application errors.
Example looks like -
class Employee {
var certificate : [Certificates]?
}
let employee = Employee();
Example 2 -
let middleName : String? = nil
let lastName : String = "Muhammad"
let name : String = middleName ?? lastName
Example looks like -
class Employee {
var certificate : [Certificates]?
}
let employee = Employee();
Example 2 -
let middleName : String? = nil
let lastName : String = "Muhammad"
let name : String = middleName ?? lastName
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