队列代表对象的先进先出集合。当您需要对项目进行先进先出的访问时,可以使用它。当您在列表中添加一个项目时,它称为enqueue ,而当您删除一个项目时,它称为deque 。队列
特性 :
- Enqueue将元素添加到队列的末尾。
- 出队从队列开始处删除最旧的元素。
- Peek返回位于队列开始处的最旧元素,但不会将其从队列中删除。
- 队列的容量是队列可以容纳的元素数。
- 随着元素添加到队列中,通过重新分配内部数组,容量会根据需要自动增加。
- 队列接受null作为引用类型的有效值,并允许重复的元素。
句法:
public T[] ToArray ();
这里T []是一个新数组,其中包含从Queue复制的元素
下面给出了一些示例,以更好地理解实现:
范例1:
// C# code to Create a Queue
// from a collection
using System;
using System.Collections.Generic;
class GFG {
// Driver code
public static void Main()
{
// Creating a Queue of strings
Queue myQueue1 = new Queue();
// Inserting the elements into the Queue
myQueue1.Enqueue("GeeksforGeeks");
myQueue1.Enqueue("is");
myQueue1.Enqueue("the");
myQueue1.Enqueue("best");
myQueue1.Enqueue("website");
// Displaying the count of elements
// contained in the myQueue1
Console.Write("Total number of elements in the Queue 1 are : ");
Console.WriteLine(myQueue1.Count);
// Displaying the elements in Queue myQueue1
foreach(string str in myQueue1)
{
Console.WriteLine(str);
}
// Creating a Queue from a collection
Queue myQueue2 = new Queue(myQueue1.ToArray());
// Displaying the count of elements
// contained in the myQueue2
Console.Write("Total number of elements in the Queue 2 are : ");
Console.WriteLine(myQueue2.Count);
// Displaying the elements in Queue myQueue2
foreach(string str in myQueue2)
{
Console.WriteLine(str);
}
}
}
输出:
Total number of elements in the Queue 1 are : 5
GeeksforGeeks
is
the
best
website
Total number of elements in the Queue 2 are : 5
GeeksforGeeks
is
the
best
website
范例2:
// C# code to Create a Queue
// from a collection
using System;
using System.Collections.Generic;
class GFG {
// Driver code
public static void Main()
{
// Creating a Queue of Integers
Queue myQueue1 = new Queue();
// Inserting the elements into the Queue
myQueue1.Enqueue(5);
myQueue1.Enqueue(10);
myQueue1.Enqueue(15);
myQueue1.Enqueue(20);
myQueue1.Enqueue(25);
// Displaying the count of elements
// contained in the myQueue1
Console.Write("Total number of elements in the Queue 1 are : ");
Console.WriteLine(myQueue1.Count);
// Displaying the elements in Queue myQueue1
foreach(int i in myQueue1)
{
Console.WriteLine(i);
}
// Creating a Queue from a collection
Queue myQueue2 = new Queue(myQueue1.ToArray());
// Displaying the count of elements
// contained in the myQueue2
Console.Write("Total number of elements in the Queue 2 are : ");
Console.WriteLine(myQueue2.Count);
// Displaying the elements in Queue myQueue2
foreach(int i in myQueue2)
{
Console.WriteLine(i);
}
}
}
输出:
Total number of elements in the Queue 1 are : 5
5
10
15
20
25
Total number of elements in the Queue 2 are : 5
5
10
15
20
25
参考:
- https://docs.microsoft.com/zh-cn/dotnet/api/system.collections.generic.queue-1.toarray?view=netframework-4.7.2