In C#, How to get the value of a variable when it changes Without threads or timers

Question

int i = 0;

When i value changes:

i = (Atypical value)

then

bool callback(int i)
   target = i;
   return true;

In C#, How to get the value of a variable when it changes Without using threads or timers

Answer 1

Use a property:

private int _i = 0;
public int i
{
    get { return _i; }
    set
    {
        if (_i == value) { return; }
        _i = value;
        callback(value);
    }
}