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.
1. // Assign value to a
2. a = value;
3. // Assign value to b if b is null; otherwise, b stays the same
4. b ??= value;
Compound assignment operators such as += combinean operation with an assignment.
= |
–= |
/= |
%= |
>>= |
^= |
+= |
*= |
~/= |
<<= |
&= |
|= |
Here’s how compound assignment operators work:
| Compound assignment | Equivalent expression | |
|---|---|---|
| For an operator op: | a op= b |
a = a op b |
| Example: | a += b |
a = a + b |
The following example uses assignment and compound assignmentoperators:
1. var a = 2; // Assign using =
2. a *= 3; // Assign and multiply: a = a * 3
3. assert(a == 6);
