在 C# 中检查 Hashtable 是否包含特定 Key
csharpserver side programmingprogramming更新于 2024/9/13 7:43:00
要检查 Hashtable 是否包含特定 Key，代码如下 −
示例
using System;
using System.Collections;
public class Demo {
public static void Main()
public static void Main(){
Hashtable hash = new Hashtable();
hash.Add("One", "Katie");
hash.Add("Two", "John");
hash.Add("Three", "Barry");
hash.Add("Four", "Mark");
hash.Add("Five","Harry");
hash.Add("Six", "Nathan");
hash.Add("Seven", "Tom");
hash.Add("Eight","Andy");
hash.Add("Nine", "Illeana");
hash.Add("Ten", "Tim");
Console.WriteLine("Hashtable Key and Value pairs...");
foreach(DictionaryEntry entry in hash){
Console.WriteLine("{0} and {1} ", entry.Key, entry.Value);
}
Console.WriteLine("Is Hashtable having fixed size? = "+hash.IsFixedSize);
Console.WriteLine("If Hashtable read-only? = "+hash.IsReadOnly);
Console.WriteLine("The Hashtable consists of the key? = "+hash.ContainsKey("Seven"));
}
}
输出
这将产生以下输出 −
Hashtable Key and Value pairs... One and Katie Ten and Tim Five and Harry Three and Barry Seven and Tom Two and John Four and Mark Eight and Andy Nine and Illeana Six and Nathan Is Hashtable having fixed size? = False If Hashtable read-only? = False The Hashtable consists of the key? = True
示例
让我们看另一个例子 −
using System;
using System.Collections;
public class Demo {
public static void Main(){
Hashtable hash = new Hashtable();
hash.Add("1", "A");
hash.Add("2", "B");
hash.Add("3", "C");
hash.Add("4", "D");
hash.Add("5","E");
hash.Add("6", "F");
hash.Add("7", "G");
hash.Add("8","H");
hash.Add("9", "I");
hash.Add("10", "J");
Console.WriteLine("Hashtable Key and Value pairs...");
foreach(DictionaryEntry entry in hash){
Console.WriteLine("{0} and {1} ", entry.Key, entry.Value);
}
Console.WriteLine("Is Hashtable having fixed size? = "+hash.IsFixedSize);
Console.WriteLine("If Hashtable read-only? = "+hash.IsReadOnly);
Console.WriteLine("The Hashtable consists of the key? = "+hash.ContainsKey("5"));
}
}
输出
这将产生以下输出 −
Hashtable Key and Value pairs... 10 and J 1 and A 2 and B 3 and C 4 and D 5 and E 6 and F 7 and G 8 and H 9 and I Is Hashtable having fixed size? = False If Hashtable read-only? = False The Hashtable consists of the key? = True
