what is difference between ref and out parameter?

Hi,

If you are passing variable as a Reference parameters, only assigned variables can be passed, it won't allow you to pass unassigned variables.
When you are passing as a out parameters you can pass unassigned variables as a parameters to method, values should be assigned in the method itself.

For Example
Reference parameters
public static void Method(ref int a,ref int b)
{
..........
}
public static void Main()
{
int a=12,b=2;
Method(ref a,ref b);
}

Out parameters
public static void Method(out int a,out int b)
{
a=10;
b=90;
....
}
public static void Main()
{
int a,b;
Method(out a,out b);
}

thanks shilpa.c