C# C# |从哈希表

C# |从哈希表

中删除带有指定键的元素

原文:https://www . geeksforgeeks . org/c-sharp-从哈希表中移除具有指定键的元素/

哈希表类表示基于键的哈希代码组织的键和值对的集合。该键用于访问集合中的项。哈希表。移除(对象)方法用于从哈希表中移除具有指定键的元素。

语法:

public virtual void Remove (object key);

参数:

键:是系统类型的元素移除键。对象。

异常:

ArgumentNullException: 如果密钥为空。
notSupportDexception:如果哈希表是只读的或具有固定的大小。

示例:

// C# code to remove the element
// with the specified key from Hashtable
using System;
using System.Collections;

class GFG {

    // Driver code
    public static void Main()
    {

        // Creating a Hashtable
        Hashtable myTable = new Hashtable();

        // Adding elements in Hashtable
        myTable.Add("2", "Even & Prime");
        myTable.Add("3", "Odd & Prime");
        myTable.Add("4", "Even & non-prime");
        myTable.Add("9", "Odd & non-prime");

        // Print the number of entries in Hashtable
        Console.WriteLine("Total number of entries in Hashtable : " 
                                                  + myTable.Count);

        // To remove the elements from Hashtable
        // which has key as "3"
        myTable.Remove("3");

        // Print the number of entries in Hashtable
        Console.WriteLine("Total number of entries in Hashtable : " 
                                                  + myTable.Count);

        // To remove the elements from Hashtable
        // which has key as "4"
        myTable.Remove("4");

        // Print the number of entries in Hashtable
        Console.WriteLine("Total number of entries in Hashtable : " 
                                                  + myTable.Count);

        // Adding elements in Hashtable
        myTable.Add("g", "geeks");
        myTable.Add("c", "c++");
        myTable.Add("d", "data structures");

        // Print the number of entries in Hashtable
        Console.WriteLine("Total number of entries in Hashtable : " 
                                                  + myTable.Count);

        // To remove the elements from Hashtable
        // which has key as "c"
        myTable.Remove("c");

        // Print the number of entries in Hashtable
        Console.WriteLine("Total number of entries in Hashtable : " 
                                                  + myTable.Count);
    }
}

Output:

Total number of entries in Hashtable : 4
Total number of entries in Hashtable : 3
Total number of entries in Hashtable : 2
Total number of entries in Hashtable : 5
Total number of entries in Hashtable : 4

参考: