EN CSharp Operator Logical

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Logical operations

Handbook C# · Practical Guide

&& and || short-circuit: they evaluate the right operand only when required. Boolean & and | evaluate both operands; ! negates and ^ is exclusive OR.

Simple example (Example.cs)

Save this example separately as Example.cs. Run it independently of the other examples on this page.

Example.cs:

// PROJECT-EXAMPLE
bool ready = true;
bool stopped = false;
System.Console.WriteLine(ready && !stopped);

Result:

True

Syntax

!condition / left && right / left || right

Example 1

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using System.IO;
using System.Runtime.InteropServices;
using System.Runtime.CompilerServices;

public static class Program
{
    public static async Task Main(string[] args)
    {
        bool ready = true, blocked = false;
        Console.WriteLine($"{!blocked}:{ready && !blocked}:{ready || blocked}:{ready ^ blocked}");
    }
}

Example 2

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using System.IO;
using System.Runtime.InteropServices;
using System.Runtime.CompilerServices;

public static class Program
{
    public static async Task Main(string[] args)
    {
        int calls = 0;
        bool Check() { calls++; return true; }
        bool shortResult = false && Check();
        bool fullResult = false & Check();
        Console.WriteLine($"{shortResult}:{fullResult}:{calls}");
    }
}

Official source: Microsoft Learn.