| 3.7.1.The short-circuit operators |
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The short-circuit AND operator is && and the short-circuit OR operator is ||. |
As described earlier, their normal counterparts are & and |. |
The normal operands will always evaluate each operand, but short-circuit versions will evaluate the second operand only when necessary. |
using System;
class Example {
public static void Main() {
int n, d;
n = 10;
d = 2;
if(d != 0 && (n % d) == 0)
Console.WriteLine(d + " is a factor of " + n);
d = 0; // now, set d to zero
Console.WriteLine("Since d is zero, the second operand is not evaluated.");
if(d != 0 && (n % d) == 0)
Console.WriteLine(d + " is a factor of " + n);
Console.WriteLine("try the same thing without short-circuit operator. This will cause a divide-by-zero error.");
if(d != 0 & (n % d) == 0)
Console.WriteLine(d + " is a factor of " + n);
}
}
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2 is a factor of 10
Since d is zero, the second operand is not evaluated.
try the same thing without short-circuit operator. This will cause a divide-by-zero error.
Unhandled Exception: System.DivideByZeroException: Attempted to divide by zero.
at Example.Main() |