LINQ基础篇（下）

分页 Skip Take

var query = DataSource.Skip((PageNo-1)*PageSize).Take(PageSize).ToList();

Skip 跳过多少个元素

Take取出多少个元素

SkipWhile 逐一判断直到不满足条件，将该元素及其后的元素取出

TakeWhile 逐一判断取出满足条件的元素

Except

语法 a.Except(b)

作用 a中去除b中元素后剩余部分

1             List<string> strListA = new List<string> { "Hello","World","C#","JavaScript","Animal"};
2             List<string> strListB = new List<string> { "Hello", "Person", "History", "Furion", "Animal" };
3             var exceptValue = strListA.Except(strListB);
4             foreach (var item in exceptValue)
5             {
6                 Console.WriteLine(item);
7             }
8             Console.ReadKey();

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Concat

语法 a.Concat(b)

作用合并a和b中的元素，不去除重复

1             List<string> strListA = new List<string> { "Hello","World","C#","JavaScript","Animal"};
2             List<string> strListB = new List<string> { "Hello", "Person", "History", "Furion", "Animal" };
3             var concatValue = strListA.Concat(strListB);
4             foreach (var item in concatValue)
5             {
6                 Console.WriteLine(item);
7             }
8             Console.ReadKey();

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Union

语法 a.Union(b)

作用合并a和b中的元素，去除重复

1             List<string> strListA = new List<string> { "Hello","World","C#","JavaScript","Animal"};
2             List<string> strListB = new List<string> { "Hello", "Person", "History", "Furion", "Animal" };
3             var unionValue = strListA.Concat(strListB);
4             foreach (var item in unionValue)
5             {
6                 Console.WriteLine(item);
7             }
8             Console.ReadKey();

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Intersect

语法 a.Intersect(b)

作用求a和b的交集

1             List<string> strListA = new List<string> { "Hello","World","C#","JavaScript","Animal"};
2             List<string> strListB = new List<string> { "Hello", "Person", "History", "Furion", "Animal" };
3             var intersectValue = strListA.Intersect(strListB);
4             foreach (var item in intersectValue)
5             {
6                 Console.WriteLine(item);
7             }
8             Console.ReadKey();

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Contains

语法 a.Contains(b)

作用类似 like ‘%b%’

1             List<string> strListA = new List<string> { "Hello","World","C#","JavaScript","Animal"};
2             List<string> strListB = new List<string> { "Hello", "Person", "History", "Furion", "Animal" };
3             var containsValue = from s in strListA where s.Contains("l") select s;
4             foreach (var item in containsValue)
5             {
6                 Console.WriteLine(item);
7             }
8             Console.ReadKey();

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