Mega Code Archive
0069 Conditional shortcut
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shortcut means once the && or || knows the value of the whole bool expression, it stops the evaluation.
For example, a && b is false if a is false regardless whether b is true or false.
Under such condition C# doesn't execute b.
shortcut is useful in the following expression:
if(i != 0 && 4/i == 2)
If i is 0 C# won't calculate 4/i, which throws DivideByZeroException.
using System;
class Program
{
static void Main(string[] args)
{
int i = 0;
if (i != 0 && 4 / i == 2)
{
Console.WriteLine("here");
}
else {
Console.WriteLine("there");
}
}
}
The output:
there
The & and | don't do the shortcut.
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