C# - Round float every time down

Question

How to round a floating point number each time to nearest integer, but only down way. I need the fastest method.

So that float 1.2 will be 1 and 1.8 will be 1 too.

1.2f will be 1.0f

1.8f will be 1.0f

Thanks!

Solution 1

Math.Floor() is your friend here.

Sample code:

using System;
using System.Text;

namespace math
{
    class Program
    {
        static void Main(string[] args)
        {
            //
            // Two values.
            //
            float value1 = 123.456F;
            float value2 = 123.987F;
            //
            // Take floors of these values.
            //
            float floor1 = (float)Math.Floor(value1);
            float floor2 = (float)Math.Floor(value2);

            //
            // Write first value and floor.
            //
            Console.WriteLine(value1);
            Console.WriteLine(floor1);
            //
            // Write second value and floor.
            //
            Console.WriteLine(value2);
            Console.WriteLine(floor2);

            return;        
        }
    }
}

Solution 2

By casting to an int, you will truncate the decimals

float f = 1.2;
int rounded = (int)f;

Solution 3

System.Math.Floor(double) should do the trick

Solution 4

Math.Ceiling(value)
Math.Floor(value); //your answer

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