c#参数为'ref',而参数声明为'value'

public static void Main(string[] args)
{
    int value = 10;
    int refValue = 20;

    Console.WriteLine("Before: value = {0}, refValue = {1}", value, refValue);

    ValuePassing(value, ref refValue);

    Console.WriteLine("After: value = {0}, refValue = {1}", value, refValue);
}

public static void ValuePassing(int value, ref int refValue)
{
    value = 30;
    refValue = 40;

    Console.WriteLine("Inside: value = {0}, refValue = {1}", value, refValue);
}

Before: value = 10, refValue = 20
Inside: value = 30, refValue = 40
After: value = 10, refValue = 40