Dictionary的基本用法

1.创建泛型哈希表，然后加入元素 

Dictionary<string,string> openWith=new Dictionary<string, string>();
            openWith.Add("txt","notepad.exe");
            openWith.Add("bmp","paint.exe");
            openWith.Add("dib","paint.exe");
            openWith.Add("rtf","wordpad.exe");

2.遍历key

 　　　foreach (string key in openWith.Keys)
            {
                Console.WriteLine("Key = {0}", key);
            }

3.遍历value

 foreach (string value in openWith.Values)
            {
                Console.WriteLine("value = {0}", value);
            }

4.遍历value, Second Method

 

Dictionary<string, string>.ValueCollection valueColl = openWith.Values;
            foreach (string s in valueColl)
            {
                Console.WriteLine("Second Method, Value = {0}", s);
            }

 

5.遍历字典

 

foreach (KeyValuePair<string, string> kvp in openWith)
            {
                Console.WriteLine("Key = {0}, Value = {1}", kvp.Key, kvp.Value);
            }

 

6.添加存在的元素

 

try
            {
                openWith.Add("txt", "winword.exe");
            }
            catch (ArgumentException)
            {
                Console.WriteLine("An element with Key = \"txt\" already exists.");
            }

 

7.删除元素

openWith.Remove("doc");
            if (!openWith.ContainsKey("doc"))
            {
                Console.WriteLine("Key \"doc\" is not found.");
            }

8.判断键存在

if (openWith.ContainsKey("bmp")) // True 
            {
                Console.WriteLine("An element with Key = \"bmp\" exists.");
            }

9.参数为其它类型

 

Dictionary<int, string[]> OtherType = new Dictionary<int, string[]>();
            OtherType.Add(1, "1,11,111".Split(','));
            OtherType.Add(2, "2,22,222".Split(','));
            Console.WriteLine(OtherType[1][2]);