ASP.NET中Dictionary的根本用法
摘要:ASP.NET中Dictionary的根本用法
ASP.NET中Dictionary的根本用法
//Dictionary位于System.Collections.Generic命名空间之下
/*
* 利用Dictionary之前必须引用System.Collections.Generic命名空间;
* 利用Dictionary时必须申明其键和值的数据类型(可认为恣意类型);
*/
//申明实例化Dictionary为dic
System.Collections.Generic.Dictionary<int, string> dic = new System.Collections.Generic.Dictionary<int, string>();
//为dic减少键和值
dic.Add(100, "quber100");
dic.Add(200, "quber200");
//反省能否存在300这个键
if (!dic.ContainsKey(300))
{
//新添加300(键)和对应的quber300(值)
dic.Add(300, "quber300");
}
//移除dic键为300的项
dic.Remove(300);
//获取dic键值对总数
int dicCount = dic.Count;
Response.Write("循环获取dic中的键和值:<br/>");
//循环获取dic中的键和值
foreach (KeyValuePair<int, string> keyDic in dic)
{
Response.Write("key:" + keyDic.Key + ",value:" + keyDic.Value + "<br/>");
}
Response.Write("<hr/><br/>");
Response.Write("循环获取dic中的键:<br/>");
//循环获取dic中的键
Dictionary<int, string>.KeyCollection keyDics = dic.Keys;
foreach (int iKey in keyDics)
{
Response.Write("key:" + iKey + "<br/>");
}
Response.Write("<hr/><br/>");
Response.Write("另一种方法循环获取dic中的键:<br/>");
//循环获取dic中的键
foreach (int iKey in dic.Keys)
{
Response.Write("key:" + iKey + "<br/>");
}
Response.Write("<hr/><br/>");
Response.Write("循环获取dic中的值:<br/>");
//循环获取dic中的值
Dictionary<int, string>.ValueCollection valueDics = dic.Values;
foreach (string strValue in valueDics)
{
Response.Write("value:" + strValue + "<br/>");
}
Response.Write("<hr/><br/>");
Response.Write("另一种方法循环获取dic中的值:<br/>");
//循环获取dic中的值
foreach (string strValue in dic.Values)
{
Response.Write("value:" + strValue + "<br/>");
}
Response.Write("<hr/><br/>");
Response.Write("获取dic中单个键和值:<br/>");
Response.Write("key:100,value:" + dic[100] + "<br/>");
Response.Write("<hr/><br/>");
Response.Write("反省dic中能否存在键(100),并前往其值dicStr:<br/>");
//反省dic中能否存在键(100),并前往其值dicStr
string dicStr = string.Empty;
if (dic.TryGetValue(100, out dicStr))
{
Response.Write("OK");
}
else
{
Response.Write("NO");
}
Response.Write("<hr/><br/>");
/*
* 利用Dictionary之前必须引用System.Collections.Generic命名空间;
* 利用Dictionary时必须申明其键和值的数据类型(可认为恣意类型);
*/
//申明实例化Dictionary为dic
System.Collections.Generic.Dictionary<int, string> dic = new System.Collections.Generic.Dictionary<int, string>();
//为dic减少键和值
dic.Add(100, "quber100");
dic.Add(200, "quber200");
//反省能否存在300这个键
if (!dic.ContainsKey(300))
{
//新添加300(键)和对应的quber300(值)
dic.Add(300, "quber300");
}
//移除dic键为300的项
dic.Remove(300);
//获取dic键值对总数
int dicCount = dic.Count;
Response.Write("循环获取dic中的键和值:<br/>");
//循环获取dic中的键和值
foreach (KeyValuePair<int, string> keyDic in dic)
{
Response.Write("key:" + keyDic.Key + ",value:" + keyDic.Value + "<br/>");
}
Response.Write("<hr/><br/>");
Response.Write("循环获取dic中的键:<br/>");
//循环获取dic中的键
Dictionary<int, string>.KeyCollection keyDics = dic.Keys;
foreach (int iKey in keyDics)
{
Response.Write("key:" + iKey + "<br/>");
}
Response.Write("<hr/><br/>");
Response.Write("另一种方法循环获取dic中的键:<br/>");
//循环获取dic中的键
foreach (int iKey in dic.Keys)
{
Response.Write("key:" + iKey + "<br/>");
}
Response.Write("<hr/><br/>");
Response.Write("循环获取dic中的值:<br/>");
//循环获取dic中的值
Dictionary<int, string>.ValueCollection valueDics = dic.Values;
foreach (string strValue in valueDics)
{
Response.Write("value:" + strValue + "<br/>");
}
Response.Write("<hr/><br/>");
Response.Write("另一种方法循环获取dic中的值:<br/>");
//循环获取dic中的值
foreach (string strValue in dic.Values)
{
Response.Write("value:" + strValue + "<br/>");
}
Response.Write("<hr/><br/>");
Response.Write("获取dic中单个键和值:<br/>");
Response.Write("key:100,value:" + dic[100] + "<br/>");
Response.Write("<hr/><br/>");
Response.Write("反省dic中能否存在键(100),并前往其值dicStr:<br/>");
//反省dic中能否存在键(100),并前往其值dicStr
string dicStr = string.Empty;
if (dic.TryGetValue(100, out dicStr))
{
Response.Write("OK");
}
else
{
Response.Write("NO");
}
Response.Write("<hr/><br/>");