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]);