The safe navigation operator(?)(or known as Elvis Operator) is used to guard against null and undefined values in property paths when you are not aware whether a path exists or not. i.e. It returns value of the object path if it exists, else it returns the null value.
For example, you can access nested properties of a user profile easily without null reference errors as below:
1 | <p>The user firstName is: {{user?.fullName.firstName}}</p> |
Using this safe navigation operator, Angular framework stops evaluating the expression when it hits the first null value and renders the view without any errors.
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