ref 在呼叫前必需先被指派。
static void main()
{ int b;
test(out b);
Response.Write(b);
int c = 5;
test2(ref c);
Response.Write(c);
}
public void test2(ref int a)
{
//a = 10;
}
public void test(out int a ) {
a = 10;
}
