C# Dictionary使用

  Dictionary<string, int> illegParking = new Dictionary<string, int>();

键:inData.LOTID

值:inData.ISILLEGPARKING

1、判断键存不存在。

dictionary中是不允许有重复项的,这样才能按key索引到唯一一个value

if (illegParking.ContainsKey(inData.LOTID))
                {
                    illegParking[inData.LOTID] = inData.ISILLEGPARKING;
                }
                else
                {
                    illegParking.Add(inData.LOTID, inData.ISILLEGPARKING);
                }

 
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2、几种遍历方式:

Dictionary<string, int> list = new Dictionary<string, int>();

   foreach (var item in list)

            {

                Console.WriteLine(item.Key + item.Value);

            }

 //通过键的集合取

            foreach (string key in list.Keys)

            {

                Console.WriteLine(key + list[key]);

            }

   //直接取值

            foreach (int val in list.Values)

            {

                Console.WriteLine(val);

            } 

 //非要采用for的方法也可

 Dictionary<string, int> list = new Dictionary<string, int>();         

   List<string> test = new List<string>(list.Keys);

            for (int i = 0; i < list.Count; i++)

            {

                Console.WriteLine(test[i] + list[test[i]]);

            }
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3、涉及到移除某个键值的时候

  不能在foreach循环里面移除,因为会导致错误:集合已修改;可能无法执行枚举操作。可以改用for循环

//dicmodels是个dictionary

List<string> keys = new List<string>(dicModels.Keys);
for (int i = keys.Count - 1; i >= 0; i--)
     {
      }

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转载自www.cnblogs.com/peterYong/p/10881869.html
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