柚子快报激活码778899分享：c#高级写法

柚子快报激活码778899分享：c#高级写法

http://yzkb.51969.com/

Linq的参考资料：https://www.cnblogs.com/liqingwen/p/5801249.html

1.判断str字符串中的逗号个数

string str = "1,2,3,4,5,6";int count = str.Count(ch => ch == ',');

2.使用 where 子句来从数组中筛选那些具有特定长度的字符串

string[] words = { "the", "quick", "brown", "fox", "jumps" };

var query = from word in words

where word.Length == 3

select word;

foreach (var word in query)

{

Console.WriteLine(word);

}

3.查询一个List>里面的一个值v是否在其里面的字典的值中

static void Main(string[] args)

{

List> listDic = new List>();

Dictionary dic = new Dictionary();

dic.Add("88", "a");

dic.Add("123", "b");

Dictionary dic2 = new Dictionary();

dic2.Add("99", "b");

listDic.Add(dic);

listDic.Add(dic2);

//ToDictionary 转换成字典

var q = listDic.SelectMany(x => x.Where(y => y.Value == "b")).ToDictionary(a =>a.Key, a =>a.Value);

foreach (var item in q)

{

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

}

Console.ReadLine();

}

 如果需要输出其对应字典在List中的下标，则

static void Main(string[] args)

{

List> listDic = new List>();

Dictionary dic = new Dictionary();

dic.Add("88", "a");

dic.Add("123", "b");

Dictionary dic2 = new Dictionary();

dic2.Add("99", "b");

listDic.Add(dic);

listDic.Add(dic2);

//要下标的话，那就只能产生新对象了。

var q = listDic.Select((x, i) => new

{

index = i,

dict = x.Where(y => y.Value.ToString() == "b")

});

foreach (var item in q)

{

Console.WriteLine("index:{0}", item.index);

foreach (var v in item.dict)

{

Console.WriteLine(v.Key + "---" + v.Value);

}

}

Console.ReadLine();

}

4.字典合并

第一种

chanceAllDic = chanceSmallDic.Concat(chanceBigDic).ToDictionary(k => k.Key, v => v.Value);

第二种

buildDic = BattleJsonData.chanceSmallDic.Union(BattleJsonData.chanceBigDic).ToDictionary(k => k.Key, v => v.Value);

5.类型转换

public static List> ListDicSort(List