C#中的Stack.Peek()方法
C#中的Stack.Peek()方法用于在不删除对象的情况下返回堆栈顶部的对象。
语法
语法如下-
public virtual object Peek ();
示例
现在让我们看一个例子-
using System;
using System.Collections;
public class Demo {
public static void Main() {
Stack stack = new Stack();
stack.Push("Inspiron");
stack.Push("Alienware");
stack.Push("Projectors");
stack.Push("Monitors");
stack.Push("XPS");
stack.Push("Laptop");
stack.Push("Notebook");
Console.WriteLine("Stack elements...");
foreach(string val in stack) {
Console.WriteLine(val);
}
Console.WriteLine("Count of elements = "+stack.Count);
Console.WriteLine("Element at the top = "+ stack.Peek());
stack.Push("Ultrabook");
stack.Push("Cameras");
stack.Push("Keyboards");
Console.WriteLine("\nStack elements...updated");
foreach(string val in stack) {
Console.WriteLine(val);
}
Console.WriteLine("Element at the top = "+ stack.Peek());
Console.WriteLine("\nCount of elements (updated) = "+stack.Count);
stack.Clear();
Console.Write("Count of elements (updated) = "+stack.Count);
}
}输出结果
这将产生以下输出-
Stack elements... Notebook Laptop XPS Monitors Projectors Alienware Inspiron Count of elements = 7 Element at the top = Notebook Stack elements...updated Keyboards Cameras Ultrabook Notebook Laptop XPS Monitors Projectors Alienware Inspiron Element at the top = Keyboards Count of elements (updated) = 10 Count of elements (updated) = 0
示例
现在让我们来看另一个示例-
using System;
using System.Collections;
public class Demo {
public static void Main() {
Stack stack = new Stack();
stack.Push("Inspiron");
stack.Push("Alienware");
stack.Push("Projectors");
stack.Push("Monitors");
stack.Push("XPS");
stack.Push("Laptop");
stack.Push("Notebook");
Console.WriteLine("Stack elements...");
foreach(string val in stack) {
Console.WriteLine(val);
}
Console.WriteLine("Count of elements = "+stack.Count);
Console.WriteLine("Element Speakers is the stack? = "+stack.Contains("Speakers"));
stack.Push("Headphone");
stack.Push("Keyboard");
stack.Push("Earphone");
Console.WriteLine("\nStack elements...updated");
foreach(string val in stack) {
Console.WriteLine(val);
}
Console.WriteLine("Count of elements (updated) = "+stack.Count);
Console.WriteLine("Element Alienware is the stack? = "+stack.Contains("Alienware"));
Stack stack2 = (Stack)stack.Clone();
Console.WriteLine("\nStack elements...cloned");
foreach(string val in stack2) {
Console.WriteLine(val);
}
Console.Write("Count of elements (updated) = "+stack2.Count);
Console.WriteLine("Top of the Stack = "+stack2.Peek());
}
}输出结果
这将产生以下输出-
Stack elements... Notebook Laptop XPS Monitors Projectors Alienware Inspiron Count of elements = 7 Element at the top = Notebook Stack elements...updated Keyboards Cameras Ultrabook Notebook Laptop XPS Monitors Projectors Alienware Inspiron Element at the top = Keyboards Count of elements (updated) = 10 Count of elements (updated) = 0