Convert C# 6.0 default propertyvalues to C# 5.0

Question

public List<string> MembershipIds
{
    get;
    set;
} = new List<string>();

I got Invalid token

"=" in class, struct or interface member declaration.

This is C# 6 feature. How to convert it to C# 5?

Answer 1

There is no easy way to do it while leaving the auto-property in place.

If you do not require an auto property, convert the code to using a private variable and a non-automatic property:

private List<string> membershipIds = new List<string>();
public List<string> MembershipIds {
    get { return membershipIds; }
    set { membershipIds = value; }
}

If you do require the auto-property, you need to make the assignment in the constructor:

public List<string> MembershipIds { get;set; }
...
// This constructor will do the assignment.
// If you do not plan to publish no-argument constructor,
// it's OK to make it private.
public MyClass() {
    MembershipIds = new List<string>();
}
// All other constructors will call the no-arg constructor
public MyClass(int arg) : this() {// Call the no-arg constructor
    .. // do other things
}
public MyClass(string arg) : this() {// Call the no-arg constructor
    .. // do other things
}