本文整理汇总了C#中System.Collections.Hashtable类的典型用法代码示例。如果您正苦于以下问题:C# Hashtable类的具体用法?C# Hashtable怎么用?C# Hashtable使用的例子?那么, 这里精选的类代码示例或许可以为您提供帮助。
Hashtable类属于System.Collections命名空间,在下文中一共展示了Hashtable类的2个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: Main
//引入命名空间
using System;
using System.Collections;
class Example
{
public static void Main()
{
// Create a new hash table.
//
Hashtable openWith = new Hashtable();
// Add some elements to the hash table. There are no
// duplicate keys, but some of the values are duplicates.
openWith.Add("txt", "notepad.exe");
openWith.Add("bmp", "paint.exe");
openWith.Add("dib", "paint.exe");
openWith.Add("rtf", "wordpad.exe");
// The Add method throws an exception if the new key is
// already in the hash table.
try
{
openWith.Add("txt", "winword.exe");
}
catch
{
Console.WriteLine("An element with Key = \"txt\" already exists.");
}
// The Item property is the default property, so you
// can omit its name when accessing elements.
Console.WriteLine("For key = \"rtf\", value = {0}.", openWith["rtf"]);
// The default Item property can be used to change the value
// associated with a key.
openWith["rtf"] = "winword.exe";
Console.WriteLine("For key = \"rtf\", value = {0}.", openWith["rtf"]);
// If a key does not exist, setting the default Item property
// for that key adds a new key/value pair.
openWith["doc"] = "winword.exe";
// ContainsKey can be used to test keys before inserting
// them.
if (!openWith.ContainsKey("ht"))
{
openWith.Add("ht", "hypertrm.exe");
Console.WriteLine("Value added for key = \"ht\": {0}", openWith["ht"]);
}
// When you use foreach to enumerate hash table elements,
// the elements are retrieved as KeyValuePair objects.
Console.WriteLine();
foreach( DictionaryEntry de in openWith )
{
Console.WriteLine("Key = {0}, Value = {1}", de.Key, de.Value);
}
// To get the values alone, use the Values property.
ICollection valueColl = openWith.Values;
// The elements of the ValueCollection are strongly typed
// with the type that was specified for hash table values.
Console.WriteLine();
foreach( string s in valueColl )
{
Console.WriteLine("Value = {0}", s);
}
// To get the keys alone, use the Keys property.
ICollection keyColl = openWith.Keys;
// The elements of the KeyCollection are strongly typed
// with the type that was specified for hash table keys.
Console.WriteLine();
foreach( string s in keyColl )
{
Console.WriteLine("Key = {0}", s);
}
// Use the Remove method to remove a key/value pair.
Console.WriteLine("\nRemove(\"doc\")");
openWith.Remove("doc");
if (!openWith.ContainsKey("doc"))
{
Console.WriteLine("Key \"doc\" is not found.");
}
}
}
输出:
An element with Key = "txt" already exists. For key = "rtf", value = wordpad.exe. For key = "rtf", value = winword.exe. Value added for key = "ht": hypertrm.exe Key = dib, Value = paint.exe Key = txt, Value = notepad.exe Key = ht, Value = hypertrm.exe Key = bmp, Value = paint.exe Key = rtf, Value = winword.exe Key = doc, Value = winword.exe Value = paint.exe Value = notepad.exe Value = hypertrm.exe Value = paint.exe Value = winword.exe Value = winword.exe Key = dib Key = txt Key = ht Key = bmp Key = rtf Key = doc Remove("doc") Key "doc" is not found.
示例2: foreach
foreach(DictionaryEntry de in myHashtable)
{
// ...
}