Assignment operators

As you’ve already seen, you can assign values using the = operator.To assign only if the assigned-to variable is null,use the ??= operator.

// Assign value to a
a = value;
// Assign value to b if b is null; otherwise, b stays the same
b ??= value;

Compound assignment operators such as += combinean operation with an assignment.

Here’s how compound assignment operators work:

The following example uses assignment and compound assignmentoperators:

var a = 2; // Assign using =
a *= 3; // Assign and multiply: a = a * 3
assert(a == 6);