C# 0 The Complete Reference

PART I

C h a p t e r   4 :  

O p e r a t o r s  

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PART IPART I

Understand, however, that in the increment or decrement forms, 

x

 is evaluated only once, 

not twice. This can improve efficiency in some cases.

Both the increment and decrement operators can either precede (prefix) or follow 

(postfix) the operand. For example

x = x + 1;

can be written as

++x; // prefix form

or as

x++; // postfix form

In the foregoing example, there is no difference whether the increment is applied as a 

prefix or a postfix. However, when an increment or decrement is used as part of a larger 

expression, there is an important difference. When an increment or decrement operator 

precedes

 its operand, the result of the operation is the value of the operand 

after

 the increment. 

If the operator 

follows

 its operand, the result of the operation is the value of the operand 

before

 the increment. Consider the following:

x = 10;

y = ++x;

In this case,