此方法用于从队列中删除对象。此方法是O(n)运算，其中n是元素总数。而且此方法位于System.Collections命名空间下。
句法：
public void Clear ();
下面给出了一些示例，以更好地理解实现：
范例1：
// C# code to illustrate the
// Queue.Clear Method
using System;
using System.Collections;
class GFG {
// Driver code
public static void Main()
{
// Creating a Queue
Queue q = new Queue();
// Inserting the elements into the Queue
q.Enqueue(1);
q.Enqueue(2);
q.Enqueue(2);
q.Enqueue(4);
// Displaying the count of elements
// contained in the Queue before
// removing all the elements
Console.Write("Total number of elements "+
"in the Queue are : ");
Console.WriteLine(q.Count);
// Removing all elements from Queue
q.Clear();
// Displaying the count of elements
// contained in the Queue after
// removing all the elements
Console.Write("Total number of elements"+
" in the Queue are : ");
Console.WriteLine(q.Count);
}
}
输出：
Total number of elements in the Queue are : 4
Total number of elements in the Queue are : 0
范例2：
// C# code to illustrate the
// Queue.Clear Method
using System;
using System.Collections;
class GFG {
// Driver code
public static void Main()
{
// Creating a Queue
Queue q = new Queue();
// Inserting the elements into the Queue
q.Enqueue("C");
q.Enqueue("C++");
q.Enqueue("Java");
q.Enqueue("PHP");
q.Enqueue("HTML");
q.Enqueue("Python");
// Displaying the count of elements
// contained in the Queue before
// removing all the elements
Console.Write("Total number of elements "+
"in the Queue are : ");
Console.WriteLine(q.Count);
// Removing all elements from Queue
q.Clear();
// Displaying the count of elements
// contained in the Queue after
// removing all the elements
Console.Write("Total number of elements "+
"in the Queue are : ");
Console.WriteLine(q.Count);
}
}
输出：
Total number of elements in the Queue are : 6
Total number of elements in the Queue are : 0
参考：
- https://docs.microsoft.com/zh-cn/dotnet/api/system.collections.queue.clear?view=netframework-4.7.2