Null-conditional operators ^{C# 6.0} allowed us to conditionally access members of an object where if the object was null then the result would also be null rather than throwing a NullReferenceException.

C# 14 allows assignment to also now be conditional using the same ?. and ?[] syntax.

Code

Now

var postToDelete = posts.FirstOrDefault(p => p.Id == postId);
postToDelete?.DeletedAt = DateTime.Now;

Before

var postToDelete = posts.FirstOrDefault(p => p.Id == postId);
if (postToDelete is not null)
{
    postToDelete.DeletedAt = DateTime.Now;
}

Notes

• The right-hand side is only evaluated when the target is not null, so customer?.Order = GetCurrentOrder() does not call GetCurrentOrder for a null customer
• Works with ?[] and with compound assignment such as += and -=
• Increment and decrement (++ and --) are not allowed

More information

• What's new in C# 14.0
• C# Reference