using System;using System.Collections.Generic;using System.Linq;using System.Text;namespace 使用Object類實(shí)現(xiàn)后進(jìn)先出隊(duì)列{ class Stack {  private Object[] _items;  public Object[] Items  {   get { return this._items; }   set { this._items = value; }  }  //將對(duì)象壓入  public void Push(Object obj)  {   //第一次壓入時(shí)，進(jìn)行初始化，長(zhǎng)度為1   if (this._items == null)   {    this._items = new Object[1];    this._items[0] = obj;   }   else   {    int count = this._items.Length;    Object[] objTemp = this._items;    this._items = new Object[count + 1];    int i = 0;    foreach (Object o in objTemp)    {     this._items[i++] = o;    }    this._items[i] = obj;   }  }  //按后入先出取出  public Object Pop()  {   //為初始化或長(zhǎng)度為0時(shí)，無(wú)法取出任何元素   if (this._items == null||this._items.Length == 0)    return null;   else   {    Object obj = this._items[this._items.Length - 1];    //刪除最后一個(gè)元素    this.DeleteLastObj();    return obj;   }  }  private void DeleteLastObj()  {   Object[] objTemp = new Object[this._items.Length - 1];   for (int i = 0; i < this._items.Length - 1; i++)   {    objTemp[i] = this._items[i];   }   this._items = objTemp;  } }}

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Windows.Forms;namespace 使用Object類實(shí)現(xiàn)后進(jìn)先出隊(duì)列{ public partial class Form1 : Form {  public Form1()  {   InitializeComponent();  }  private Stack stack = new Stack();  private Stack<string> stackGeneric= new Stack<string>();  private void button1_Click(object sender, EventArgs e)  {   stack.Push(this.textBox1.Text);  }  private void button2_Click(object sender, EventArgs e)  {   Object[] objs = stack.Items;   foreach(Object o in objs)   {    Console.WriteLine(o.ToString());   }  }  private void button1_Click_1(object sender, EventArgs e)  {   try   {    Console.WriteLine(this.stack.Pop().ToString());   }   catch   {    Console.WriteLine("null");   }  }  private void button3_Click(object sender, EventArgs e)  {   this.stackGeneric.Push(this.textBox2.Text);  }  private void button4_Click(object sender, EventArgs e)  {   try   {    Console.WriteLine(this.stackGeneric.Pop());   }   catch (InvalidOperationException)   {    Console.WriteLine("null");   }  } }}