C#栈的实现（数制转换）

using System ;
public class Stacks
{
private object [] _array; //存放元素的数组；
private const int _defaultCapacity=10; //默认空间；
private int _size; //指示元素个数；
public Stacks ()
{
this._array=new object[_defaultCapacity] ;
this._size=0;
}
public Stacks(int initalCapacity)
{
if(initalCapacity <0)
{
throw new ArgumentOutOfRangeException("栈空间不能小于0！");
}
if(initalCapacity <_defaultCapacity )
{
initalCapacity =_defaultCapacity ;
}
this._array=new object[initalCapacity] ; //分配栈空间；
this._size=0;
}
//出栈；
public object Pop()
{
if(this._size==0)
{
throw new InvalidOperationException("栈下溢，栈内已无数据！");
}
object obj2=this._array[--this._size]; //取出栈顶元素；
this._array[this._size]=null; //删除栈顶元素；
return obj2;
}
//进栈；
public void Push(object obj)
{
if(this._size==this._array.Length)
{
//如果栈空间已满，则将原来空间扩展为原来的2倍；
object[]destinationArray=new object[2*this._array.Length];
Array.Copy(this._array,0,destinationArray ,0,this._size);
this._array=destinationArray;
}
}
public int Count
{
get {return this._size;}
}
}
class App
{
static string DecConvert(int N,int D)
{
if(D<2||D>16)
{
throw new ArgumentOutOfRangeException("D","只支持将十进制数据转换为二进制至16进制！");
}
Stacks stack=new Stacks ();
do
{
int residue=N%D;//取余；
char c=(residue <10)?(char)(residue+48):(char)(residue+55);
stack.Push(c); //进栈；
}
while ((N=N/D)!=0);

string s=string.Empty;
while (stack.Count>0)
{
s+=stack.Pop().ToString();
}
return s;
}
static void Main()
{
Console.WriteLine(DecConvert(27635,16));
Console.WriteLine(DecConvert(27635,8));
Console.WriteLine(DecConvert(27635,2));
}
}