C# - Restrict double variable to two decimal places

I am using Unity Engine to make a game.
I am using a double variable and want it to only display the number till two decimal places.

public double nos = 0;

For eg: if nos = 17.2369...;
I want it to display nos = 17.23;

P.S.: I don't want to round it off or smt.

How to make that happen?

You are right, string formatting also does some rounding.
This should work then:

double num = 15.345324;
num = Math.Truncate(100 * num) / 100;
// num = 15.34

Use 10 to the power of decimal places (here: 100) you want to have as factor.

100 -> 2dps

1000 -> 3dps

etc.

Edit: In a more general way one could do sth like this

double num = 12.3456789;
double numOfDecimals = 2;
num = Math.Truncate(Math.Pow(10, numOfDecimals) * num) / Math.Pow(10, numOfDecimals);