What do these ( += , -= , *= , /= ) Operators Mean? [closed]

Question

I have been looking everywhere to figure out what these mean and how they are used +=, -=, *=, /=, the most I have found is that they are, "Assignment by Addition", "Assignment by Difference", "Assignment by Product", "Assignment by Quotient", etc, but I can't figure out when or how they are used. If anyone can please explain this to me I would be very grateful. thanks

Answer 1

They are shorthand:

a += b

is the same as

a = a + b

Etc...

so

• a -= b is equivalent to a = a - b
• a *= b is equivalent to a = a * b
• a /= b is equivalent to a = a / b

As Kevin Brydon suggested - Familiarize yourself with the operators in C# here.

Answer 2

See 7.13 Assignment operators in the spec and its subsections., specifically 7.13.2 Compound assignment:

An operation of the form x op= y is processed by applying binary operator overload resolution (Section 7.2.4) as if the operation was written x op y. Then,

•If the return type of the selected operator is implicitly convertible to the type of x, the operation is evaluated as x = x op y, except that x is evaluated only once.

•Otherwise, if the selected operator is a predefined operator, if the return type of the selected operator is explicitly convertible to the type of x, and if y is implicitly convertible to the type of x, then the operation is evaluated as x = (T)(x op y), where T is the type of x, except that x is evaluated only once.

•Otherwise, the compound assignment is invalid, and a compile-time error occurs.

Answer 3

a+=1 means a = a+1
a-=2 means a = a-2
a*=3 means a = a*3
a/=4 means a = a/4

Answer 4

These are Assignment operators(Shorthands)

a += 1; is equal to a =  a + 1;

b -= 1; is equal to b =  b - 1;

a *= 1; is equal to a =  a * 1;

b /= 1; is equal to b =  b / 1;

Refer:Link