\u63d0\u4f9b\u4e00\u7ec4\u9759\u6001\u65b9\u6cd5\u7528\u4e8e\u67e5\u8be2\u5b9e\u73b0IEnumerable<T>\u7684\u5bf9\u8c61\u3002<\/p>\n\n\n\n
\u5728\u5e8f\u5217\u4e0a\u5e94\u7528\u7d2f\u52a0\u5668\u51fd\u6570\u3002\u6307\u5b9a\u7684\u503c\u4f5c\u4e3a\u521d\u59cb\u7d2f\u52a0\u5668\u503c\uff0c\u6307\u5b9a\u7684\u51fd\u6570\u7528\u4e8e\u9009\u62e9\u7ed3\u679c\u3002<\/p>\n\n\n\n
List<String> fruits = new List<string>();\nfruits.AddRange(new string[] { \"apple\", \"mango\", \"orange\", \"passionfruit\"});\nstring longestName = fruits.Aggregate(\"banana\", (longest, next) => next.Length > longest.Length ? next : longest, fruit => fruit.ToUpper());\nConsole.WriteLine(\"the fruit with longest name is {0}.\", longestName);\n\/\/the fruit with longest name is PASSIONFRUIT.<\/code><\/pre>\n\n\n\n2.All<\/h3>\n\n\n\n
\u5224\u65ad\u5e8f\u5217\u7684\u6240\u6709\u503c\u662f\u5426\u90fd\u6ee1\u8db3\u7279\u5b9a\u6761\u4ef6\u3002<\/p>\n\n\n\n
public class Pet {\n public string Name {\n get;\n set;\n }\n public int Age {\n get;\n set;\n }\n}\n\npublic class Person {\n public string LastName {\n get;\n set;\n }\n public Pet[] Pets {\n get;\n set;\n }\n}<\/code><\/pre>\n\n\n\nList<Person> people = new List<Person>{\n new Person{LastName = \"Haas\", Pets =\n new Pet[]{\n new Pet{Name = \"Barley\", Age = 10},\n new Pet{Name = \"Boots\", Age = 14},\n new Pet{Name = \"Whiskers\", Age = 6},\n }},\n new Person{\n LastName = \"Fakhouri\",\n Pets =\n new Pet[]{\n new Pet{Name = \"Snowball\", Age = 1},\n },\n },\n new Person{LastName = \"Antebi\", Pets =\n new Pet[]{\n new Pet{Name = \"Belle\", Age = 8},\n }},\n new Person{LastName = \"Philips\", Pets = new Pet[]{\n new Pet{Name = \"Sweetie\", Age = 2},\n new Pet{Name = \"Rover\", Age = 13},\n }}};\n\/\/\u7b5b\u9009\u6240\u6709\u5ba0\u7269\u5e74\u9f84\u5927\u4e8e5\u7684\u6240\u6709\u4eba\nIEnumerable<string> allownpetgt5names =\n from person in people where\n person.Pets.All(pet => pet.Age > 5) select person.LastName;\nforeach (string name in allownpetgt5names) {\n Console.WriteLine(name);\n}\n\/\/ All\nConsole.WriteLine(\"all pet`s age >5: {0}\",\n people[0].Pets.All(i => i.Age > 5)); \/\/ True<\/code><\/pre>\n\n\n\n3.Any<\/h3>\n\n\n\nList<Person> people = new List<Person>{\n new Person{LastName = \"Haas\", Pets =\n new Pet[]{\n new Pet{Name = \"Barley\", Age = 10},\n new Pet{Name = \"Boots\", Age = 14},\n new Pet{Name = \"Whiskers\", Age = 6},\n }},\n new Person{\n LastName = \"Fakhouri\",\n Pets =\n new Pet[]{\n new Pet{Name = \"Snowball\", Age = 1},\n },\n },\n new Person{LastName = \"Antebi\", Pets =\n new Pet[]{\n new Pet{Name = \"Belle\", Age = 8},\n }},\n new Person{LastName = \"Philips\", Pets = new Pet[]{\n new Pet{Name = \"Sweetie\", Age = 2},\n new Pet{Name = \"Rover\", Age = 13},\n }}};\n\/\/\u7b5b\u9009\u6240\u6709\u5ba0\u7269\u5e74\u9f84\u5927\u4e8e5\u7684\u6240\u6709\u4eba\nIEnumerable<string> allownpetgt5names =\n from person in people where\n person.Pets.All(pet => pet.Age > 5) select person.LastName;\nforeach (string name in allownpetgt5names) {\n Console.WriteLine(name);\n}\n\/\/ Any\nConsole.WriteLine(\"any pet`s age >5: {0}\",\n people[3].Pets.Any(i => i.Age > 5)); \/\/ True<\/code><\/pre>\n\n\n\n4.Append<\/h3>\n\n\n\nList<int> numbers = new List<int>{1, 2, 3, 4};\nnumbers.Append(5);\nConsole.WriteLine(string.Join(\",\", numbers)); \/\/ 1,2,3,4\nConsole.WriteLine(string.Join(\",\", numbers.Append(5))); \/\/ 1,2,3,4,5\nList<int> newNumbers = numbers.Append(5).ToList();\nConsole.WriteLine(string.Join(\",\", newNumbers)); \/\/ 1,2,3,4,5<\/code><\/pre>\n\n\n\n5.AsEnumerable<\/h3>\n\n\n\nclass Clump<T> : List<T> {\r\n public IEnumerable<T> Where(Func<T, bool> predicate) {\r\n Console.WriteLine(\"In Clump`s implmentation of Where().\");\r\n return Enumerable.Where(this, predicate);\r\n }\r\n}<\/code><\/pre>\n\n\n\nClump<string> fruitClump =\n new Clump<string>{\"apple\", \"passionfruit\", \"banana\", \"mongo\",\n \"orange\", \"blueberry\", \"grape\", \"strawberry\"};\n\/\/ first: call clump`s Where() method with a predicate\nIEnumerable<string> query1 = fruitClump.Where(fruit => fruit.Contains(\"o\"));\n\/\/ second: first call AsEnumerable() to hide Clump`s Where() method and thereby\n\/\/ force System.Linq.Enumerable`s Where() method to be called.\nIEnumerable<string> query2 =\n fruitClump.AsEnumerable().Where(fruit => fruit.Contains(\"o\"));<\/code><\/pre>\n\n\n\n6.Average<\/h3>\n\n\n\nlong ? [] longs = {null, 10007L, 37L, 399846234235L};\ndouble ? average = longs.Average();\nConsole.WriteLine(\"The average is {0}.\", average);<\/code><\/pre>\n\n\n\n7.Cast<\/h3>\n\n\n\nSystem.Collections.ArrayList fruits2 = new System.Collections.ArrayList();\nfruits2.Add(\"mongo\");\nfruits2.Add(\"apple\");\nfruits2.Add(\"lemon\");\nIEnumerable<string> query =\n fruits2.Cast<string>().OrderBy(fruit => fruit).Select(fruit => fruit);\n\/\/\u4e0b\u9762\u7684\u4ee3\u7801\u6ca1\u6709cast\u65e0\u6cd5\u7f16\u8bd1\u901a\u8fc7\n\/\/ IEnumerable<string> query = fruits2.OrderBy(fruit => fruit).Select(fruit =>\n\/\/ fruit);\nforeach (string fruit in query) {\n Console.WriteLine(fruit);\n}<\/code><\/pre>\n\n\n\n8.Chunk \u5206\u5757\u548c\u5206\u5757\u5e76\u884c<\/h3>\n\n\n\nvar list = Enumerable.Range(1, 100); \/\/ 1-100\nvar chunkSize = 10;\nforeach (var chunk in list.Chunk(\n chunkSize)) \/\/ 1-10,11-20,21-30,31-40,41-50,51-60...91-100\n{\n Console.WriteLine(\"=>\");\n foreach (var item in chunk) {\n Console.WriteLine(item);\n }\n}\nforeach (var chunk in list.Chunk(\n chunkSize)) \/\/ 1-10,11-20,21-30,31-40,41-50,51-60...91-100\n{\n Console.WriteLine(\"=>\");\n Parallel.ForEach(chunk, (item) => { Console.WriteLine(item); });\n}<\/code><\/pre>\n\n\n\n9.Concat<\/h3>\n\n\n\nstatic Pet[] GetCats() {\n Pet[] pets = {\n new Pet{Name = \"Barley\", Age = 8},\n new Pet{Name = \"Boots\", Age = 4},\n new Pet{Name = \"Whiskers\", Age = 1},\n };\n return pets;\n}\n\nstatic Pet[] GetDogs() {\n Pet[] pets = {\n new Pet{Name = \"Bounder\", Age = 3},\n new Pet{Name = \"Snoopy\", Age = 14},\n new Pet{Name = \"Fido\", Age = 9},\n };\n return pets;\n}<\/code><\/pre>\n\n\n\nPet[] cats = GetCats();\nPet[] dogs = GetDogs();\nIEnumerable<string> query =\n cats.Select(cat => cat.Name).Concat(dogs.Select(dog => dog.Name));\nforeach (string name in query) {\n Console.WriteLine(name);\n}<\/code><\/pre>\n\n\n\n10.Contains<\/h3>\n\n\n\nlong[] ls = new long[]{1L, 2L, 5L, 7L};\nConsole.WriteLine(\"is contains 5L: {0}\", ls.Contains(5L));\nConsole.WriteLine(\"is contains 5L: {0}\", Enumerable.Contains(ls, 5L));<\/code><\/pre>\n\n\n\n11.Count<\/h3>\n\n\n\nlong[] ls = new long[]{1, 2, 3, 4, 5, 6};\nConsole.WriteLine(\"count: {0}\", ls.Count());\nConsole.WriteLine(\"count: {0}\", Enumerable.Count(ls));<\/code><\/pre>\n\n\n\n12.DefaultIfEmpty<\/h3>\n\n\n\n\/\/ non-empty sequence\nList<Pet> pets = new List<Pet>{new Pet{Name = \"Barley\", Age = 8},\n new Pet{Name = \"Boots\", Age = 4},\n new Pet{Name = \"Whiskers\", Age = 1}};\nforeach (Pet pet in pets.DefaultIfEmpty()) {\n Console.WriteLine(pet.Name); \/\/ Barley Boots Whiskers\n}\n\/\/ empty sequence\nList<int> numbers = new List<int>();\nforeach (int number in numbers.DefaultIfEmpty()) {\n Console.WriteLine(number); \/\/ 0\n}<\/code><\/pre>\n\n\n\n13.Distinct \u901a\u8fc7Comparer\u53bb\u91cd<\/h3>\n\n\n\nProduct[] products = new Product[]{new Product{Name = \"apple\", Code = 8},\n new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"orange\", Code = 4},\n new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"lemon\", Code = 12}};\nforeach (Product product in products)\n Console.WriteLine(\"name: {0}, code: {1}\", product.Name, product.Code);\n\/*\n * name: apple, code: 8\n name: apple, code: 9\n name: orange, code: 4\n name: apple, code: 9\n name: lemon, code: 12\n *\/\nIEnumerable<Product> noduplicates = products.Distinct(new ProductComparer());\nforeach (Product product in noduplicates)\n Console.WriteLine(\"name: {0}, code: {1}\", product.Name, product.Code);\n\/*\n * name: apple, code: 8\n name: apple, code: 9\n name: orange, code: 4\n name: lemon, code: 12\n*\/<\/code><\/pre>\n\n\n\nclass ProductComparer : IEqualityComparer<Product> {\n \/\/ Products are equal if their names and product number are equal.\n public bool Equals(Product x, Product y) {\n \/\/ check whether the compared objects reference the same data.\n if (Object.ReferenceEquals(x, y)) return true;\n \/\/ check whether any of the compared objects is null.\n if (Object.ReferenceEquals(x, null) || Object.ReferenceEquals(y, null))\n return false;\n \/\/ check whether the products properties are equal.\n return x.Code == y.Code && x.Name == y.Name;\n }\n\n \/\/ if Equals() returns true for a pair of objects\n \/\/ then GetHashCode() must return the same value for these objects.\n public int GetHashCode([ DisallowNull ] Product obj) {\n \/\/ Check wheather the object is null\n if (Object.ReferenceEquals(obj, null)) return 0;\n \/\/ Get hash code for the Name field if it is not null\n int hashProductName = obj.Name == null ? 0 : obj.Name.GetHashCode();\n \/\/ Get hash code for the Code field\n int hashProductCode = obj.Code.GetHashCode();\n \/\/ Calculate the hash code for the product.\n return hashProductName ^ hashProductCode;\n }\n}<\/code><\/pre>\n\n\n\n14.DistinctBy \u901a\u8fc7func\u53bb\u91cd<\/h3>\n\n\n\nProduct[] collectionWithDuplicates = new Product[]{\n new Product{Name = \"good\", Code = 9}, new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"orange\", Code = 4},\n new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"lemon\", Code = 12}};\nvar uniqueCollection =\n collectionWithDuplicates.DistinctBy(x => x.Name).ToList();\nforeach (Product product in uniqueCollection)\n Console.WriteLine(\"name: {0}, code: {1}\", product.Name, product.Code);\n\/*\n * name: good, code: 9\n * name: orange, code: 5\n name: apple, code: 9\n name: lemon, code: 12\n *\/<\/code><\/pre>\n\n\n\n15.ElementAt<\/h3>\n\n\n\nint[] ints = new int[]{\n 1, 2, 3, 4, 5,\n};\nConsole.WriteLine(ints.ElementAt(3)); \/\/ 4<\/code><\/pre>\n\n\n\n16.ElementAtOrDefault<\/h3>\n\n\n\nint[] ints = new int[]{\n 1, 2, 3, 4, 5,\n};\nConsole.WriteLine(ints.ElementAtOrDefault(5)); \/\/ 0<\/code><\/pre>\n\n\n\n17.Empty \u8fd4\u56de\u6307\u5b9a\u7c7b\u578b\u7684\u7a7a\u5e8f\u5217<\/h3>\n\n\n\nIEnumerable<decimal> empty = Enumerable.Empty<decimal>();<\/code><\/pre>\n\n\n\n18.Except \u4ea7\u751f\u4e24\u4e2a\u5e8f\u5217\u7684\u96c6\u5408\u5dee<\/h3>\n\n\n\nint[] ints1 = new int[]{\n 1, 2, 3, 4, 5,\n};\nint[] ints2 = new int[]{\n 1, 2, 0, 3, 6,\n};\nConsole.WriteLine(JsonConvert.SerializeObject(\n Enumerable.Except(ints1, ints2))); \/\/[4,5] ints1\u4e2d\u6392\u9664ints2<\/code><\/pre>\n\n\n\n19.ExceptBy<\/h3>\n\n\n\nProduct[] products1 = new Product[]{new Product{Name = \"blueberry\", Code = 9},\n new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"orange\", Code = 4},\n new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"lemon\", Code = 12}};\nProduct[] products2 = new Product[]{new Product{Name = \"mongo\", Code = 9},\n new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"orange\", Code = 4},\n new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"lemon\", Code = 12}};\n\/\/ Enumerable.ExceptBy(products1, products2, ProductNameSelector);\nforeach (Product product in products1.ExceptBy(\n products2.Select(ProductNameSelector),\n ProductNameSelector)) \/\/ products.ExceptBy(names, NameSelector)\n{\n Console.WriteLine(\"name: {0}, code: {1}\", product.Name,\n product.Code); \/\/ name: blueberry, code: 9\n}<\/code><\/pre>\n\n\n\nstatic string ProductNameSelector(Product product) => product.Name;<\/code><\/pre>\n\n\n\n20.First<\/h3>\n\n\n\nint[] ints1 = new int[]{\n 1, 2, 3, 4, 5,\n};\nConsole.WriteLine(\"first: {0}\", ints1.First()); \/\/ 1<\/code><\/pre>\n\n\n\n21.FirstOrDefault<\/h3>\n\n\n\nint[] ints1 = new int[]{};\nConsole.WriteLine(\"first: {0}\", ints1.FirstOrDefault()); \/\/ 0<\/code><\/pre>\n\n\n\n22.GroupBy<\/h3>\n\n\n\n\/\/ Create a list of pets.\nList<Pet2> petsList = new List<Pet2>{new Pet2{Name = \"Barley\", Age = 8.3},\n new Pet2{Name = \"Boots\", Age = 4.9},\n new Pet2{Name = \"Whiskers\", Age = 1.5},\n new Pet2{Name = \"Daisy\", Age = 4.3}};\n\n\/\/ Group Pet.Age values by the Math.Floor of the age.\n\/\/ Then project an anonymous type from each group\n\/\/ that consists of the key, the count of the group's\n\/\/ elements, and the minimum and maximum age in the group.\nvar query = petsList.GroupBy(\n pet => Math.Floor(pet.Age), \/\/@1\n pet => pet.Age,\n (baseAge, ages) =>\n new {Key = baseAge, \/\/@1\n Count = ages.Count(), Min = ages.Min(), Max = ages.Max()});\nConsole.WriteLine(JsonConvert.SerializeObject(query));\n\n\/\/ Iterate over each anonymous type.\nforeach (var result in query) {\n Console.WriteLine(\"\\nAge group: \" + result.Key);\n Console.WriteLine(\"Number of pets in this age group: \" + result.Count);\n Console.WriteLine(\"Minimum age: \" + result.Min);\n Console.WriteLine(\"Maximum age: \" + result.Max);\n}\n\n\/* This code produces the following output:\n\n Age group: 8\n Number of pets in this age group: 1\n Minimum age: 8.3\n Maximum age: 8.3\n\n Age group: 4\n Number of pets in this age group: 2\n Minimum age: 4.3\n Maximum age: 4.9\n\n Age group: 1\n Number of pets in this age group: 1\n Minimum age: 1.5\n Maximum age: 1.5\n*\/<\/code><\/pre>\n\n\n\n23.IntersectBy<\/h3>\n\n\n\nint[] ints1 = new int[]{\n 1, 2, 3, 4, 5,\n};\nint[] ints2 = new int[]{\n 1, 2, 0, 3, 6,\n};\nConsole.WriteLine(\n JsonConvert.SerializeObject(Enumerable.Intersect(ints1, ints2))); \/\/[1,2,3]\nProduct[] products1 = new Product[]{new Product{Name = \"blueberry\", Code = 9},\n new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"orange\", Code = 4},\n new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"lemon\", Code = 12}};\nProduct[] products2 = new Product[]{new Product{Name = \"mongo\", Code = 9},\n new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"orange\", Code = 4},\n new Product{Name = \"apple\", Code = 9},\n new Product{Name = \"lemon\", Code = 12}};\nConsole.WriteLine(JsonConvert.SerializeObject(\n Enumerable.Intersect(products1, products2, new ProductComparer())));\n\/\/[{\"Name\":\"apple\",\"Code\":9},{\"Name\":\"orange\",\"Code\":4},{\"Name\":\"lemon\",\"Code\":12}]<\/code><\/pre>\n\n\n\n24.Join<\/h3>\n\n\n\nPerson3 magnus = new Person3{Name = \"Hedlund, Magnus\"};\nPerson3 terry = new Person3{Name = \"Adams, Terry\"};\nPerson3 charlotte = new Person3{Name = \"Weiss, Charlotte\"};\n\nPet3 barley = new Pet3{Name = \"Barley\", Owner = terry};\nPet3 boots = new Pet3{Name = \"Boots\", Owner = terry};\nPet3 whiskers = new Pet3{Name = \"Whiskers\", Owner = charlotte};\nPet3 daisy = new Pet3{Name = \"Daisy\", Owner = magnus};\n\nList<Person3> people3 = new List<Person3>{magnus, terry, charlotte};\nList<Pet3> pets3 = new List<Pet3>{barley, boots, whiskers, daisy};\n\n\/\/ create a list of person-pet pairs where\n\/\/ each element is an anonymous type that contains a\n\/\/ pet`s name and the name of the person that owns the pet\n\/\/ Join<TOuter,TInner,TKey,TResult>(IEnumerable<TOuter>, IEnumerable<TInner>,\n\/\/ Func<TOuter,TKey>, Func<TInner,TKey>, Func<TOuter,TInner,TResult>)\nvar query = people3.Join(\n pets3, person => person, pet => pet.Owner,\n (person, pet) => new {OwnerName = person.Name, Pet = pet.Name});\nforeach (var obj in query) {\n Console.WriteLine(\"{0} - {1}\", obj.OwnerName, obj.Pet);\n}<\/code><\/pre>\n\n\n\n25.Last<\/h3>\n\n\n\nvar a = new string[] { \"123\", \"123\", \"123\", \"333\" };\nConsole.WriteLine(a.Last());\/\/333<\/code><\/pre>\n\n\n\n26.LastOrDefault<\/h3>\n\n\n\nvar a = new string[] { };\nConsole.WriteLine(a.LastOrDefault());\/\/ <\/code><\/pre>\n\n\n\n27.LongCount<\/h3>\n\n\n\n
Pet[] pets = {
new Pet{Name = “Barley”, Age = 8},
new Pet{Name = “Boots”, Age = 4},
new Pet{Name = “Whiskers”, Age = 1},
};
const int Age = 3;
long count = pets.LongCount(pet => pet.Age > Age);
Console.WriteLine(“There are {0} animals over age {1}.”, count, Age);<\/p>\n\n\n\n
28.Max<\/h3>\n\n\n\nvar a = new int[] { 1, 3, 2 };\nConsole.WriteLine(\"the max: {0}\", a.Max());<\/code><\/pre>\n\n\n\n29.MaxBy<\/h3>\n\n\n\nPet[] pets = {\n new Pet{Name = \"Barley\", Age = 8},\n new Pet{Name = \"Boots\", Age = 4},\n new Pet{Name = \"Whiskers\", Age = 1},\n};\nConsole.WriteLine(\"the max: {0}\",\n JsonConvert.SerializeObject(pets.MaxBy(pet => pet.Age)));\nConsole.WriteLine(\"the max: {0}\",\n JsonConvert.SerializeObject(pets.MaxBy(pet => pet,\n new MyPetComparer())));<\/code><\/pre>\n\n\n\npublic class MyPetComparer : IComparer<Pet> {\n int IComparer<Pet>.Compare(Pet? x, Pet? y) { return x.Age - y.Age; }\n}<\/code><\/pre>\n\n\n\n30.Min<\/h3>\n\n\n\nvar a = new int[] { 1, 3, 2 };\nConsole.WriteLine(\"the min: {0}\", a.Min());<\/code><\/pre>\n\n\n\n31.MinBy<\/h3>\n\n\n\nPet[] pets = {\n new Pet{Name = \"Barley\", Age = 8},\n new Pet{Name = \"Boots\", Age = 4},\n new Pet{Name = \"Whiskers\", Age = 1},\n};\nConsole.WriteLine(\"the min: {0}\",\n JsonConvert.SerializeObject(pets.MinBy(pet => pet.Age)));\nConsole.WriteLine(\"the min: {0}\",\n JsonConvert.SerializeObject(pets.MinBy(pet => pet,\n new MyPetComparer())));<\/code><\/pre>\n\n\n\npublic class MyPetComparer : IComparer<Pet> {\n int IComparer<Pet>.Compare(Pet? x, Pet? y) { return x.Age - y.Age; }\n}<\/code><\/pre>\n\n\n\n32.OfType<\/h3>\n\n\n\nArrayList mixedList = new ArrayList();\nmixedList.Add(0);\nmixedList.Add(\"Gnanavel Sekar\");\nmixedList.Add(\"Two\");\nmixedList.Add(3);\nmixedList.Add(3.21f);\nmixedList.Add(new Pet{Name = \"Whiskers\", Age = 1});\nvar stringResult = from s in mixedList.OfType<string>() select s;\nforeach (var item in stringResult) {\n Console.WriteLine(item);\n}\n\/*\n * Gnanavel Sekar\n * Two\n *\/\nvar intResult = from s in mixedList.OfType<int>() select s;\nforeach (var item in intResult) {\n Console.WriteLine(item);\n}\n\/*\n * 0\n * 3\n *\/<\/code><\/pre>\n\n\n\n33.OrderBy \u5347\u5e8f<\/h3>\n\n\n\nPet[] pets = {\n new Pet{Name = \"Barley\", Age = 8},\n new Pet{Name = \"Boots\", Age = 4},\n new Pet{Name = \"Whiskers\", Age = 1},\n};\nConsole.WriteLine(JsonConvert.SerializeObject(pets.OrderBy(pet => pet.Age)));\nConsole.WriteLine(\n JsonConvert.SerializeObject(pets.OrderBy(pet => pet, new MyPetComparer())));<\/code><\/pre>\n\n\n\npublic class MyPetComparer : IComparer<Pet> {\n int IComparer<Pet>.Compare(Pet? x, Pet? y) { return x.Age - y.Age; }\n}<\/code><\/pre>\n\n\n\n34.OrderByDescending \u964d\u5e8f<\/h3>\n\n\n\nPet[] pets = {\n new Pet{Name = \"Barley\", Age = 8},\n new Pet{Name = \"Boots\", Age = 4},\n new Pet{Name = \"Whiskers\", Age = 1},\n};\nConsole.WriteLine(\n JsonConvert.SerializeObject(pets.OrderByDescending(pet => pet.Age)));\nConsole.WriteLine(JsonConvert.SerializeObject(\n pets.OrderByDescending(pet => pet, new MyPetComparer())));<\/code><\/pre>\n\n\n\npublic class MyPetComparer : IComparer<Pet> {\n int IComparer<Pet>.Compare(Pet? x, Pet? y) { return x.Age - y.Age; }\n}<\/code><\/pre>\n\n\n\n35.Prepend \u5411\u524d\u8ffd\u52a0<\/h3>\n\n\n\nList<int> numbers = new List<int>{1, 2, 3, 4};\nnumbers.Prepend(0);\nConsole.WriteLine(JsonConvert.SerializeObject(numbers)); \/\/ 1,2,3,4\nConsole.WriteLine(JsonConvert.SerializeObject(numbers.Prepend(0))); \/\/ 0,1,2,3,4\nList<int> newNumbers = numbers.Prepend(0).ToList();\nConsole.WriteLine(JsonConvert.SerializeObject(newNumbers)); \/\/ 0,1,2,3,4<\/code><\/pre>\n\n\n\n36.Range<\/h3>\n\n\n\nIEnumerable<int> squares = Enumerable.Range(1, 10).Select(x => x * x);\nforeach (int num in squares) {\n Console.WriteLine(num);\n}<\/code><\/pre>\n\n\n\n37.Repeat \u751f\u6210\u591a\u4e2a\u76f8\u540c\u91cd\u590d\u503c\u7684\u5e8f\u5217<\/h3>\n\n\n\nIEnumerable<string> strs = Enumerable.Repeat(\"I like programming.\", 15);\nforeach (String str in strs) {\n Console.WriteLine(str);\n}<\/code><\/pre>\n\n\n\n38.Reverse<\/h3>\n\n\n\nList<int> numbers = new List<int>{1, 2, 3, 4};\nnumbers.Reverse();\nConsole.WriteLine(JsonConvert.SerializeObject(numbers)); \/\/ 4,3,2,1<\/code><\/pre>\n\n\n\n39.Select<\/h3>\n\n\n\nstring[] fruits3 = {\"apple\", \"banana\", \"mango\",\n \"orange\", \"passionfruit\", \"grape\"};\nvar query = fruits3.Select((fruit, index) =>\n new {index, str = fruit.Substring(0, index)});\nforeach (var obj in query) {\n Console.WriteLine(\"{0}\", obj);\n}<\/code><\/pre>\n\n\n\n40.SelectMany<\/h3>\n\n\n\nPetOwner[] petOwners = new PetOwner[]{\n new PetOwner{Name = \"Higa\", Pets = new List<string>{\"Scruffy\", \"Sam\"}},\n new PetOwner{Name = \"Ashkenazi\",\n Pets = new List<string>{\"Walker\", \"Sugar\"}},\n new PetOwner{Name = \"Price\",\n Pets = new List<string>{\"Scratches\", \"Diesel\"}},\n new PetOwner{Name = \"Hines\", Pets = new List<string>{\"Dusty\"}},\n};\nvar query1 = petOwners.SelectMany(\n petOwner => petOwner.Pets,\n (petOwner, petName) => new {petOwner, petName}); \/\/\u5c06petOwner.Pets\u5c55\u5f00\nConsole.WriteLine(JsonConvert.SerializeObject(query1));\n\/*\n * [\n * {\"petOwner\":{\"Name\":\"Higa\",\"Pets\":[\"Scruffy\",\"Sam\"]},\"petName\":\"Scruffy\"},\n * {\"petOwner\":{\"Name\":\"Higa\",\"Pets\":[\"Scruffy\",\"Sam\"]},\"petName\":\"Sam\"},\n * {\"petOwner\":{\"Name\":\"Ashkenazi\",\"Pets\":[\"Walker\",\"Sugar\"]},\"petName\":\"Walker\"},\n * {\"petOwner\":{\"Name\":\"Ashkenazi\",\"Pets\":[\"Walker\",\"Sugar\"]},\"petName\":\"Sugar\"},\n * {\"petOwner\":{\"Name\":\"Price\",\"Pets\":[\"Scratches\",\"Diesel\"]},\"petName\":\"Scratches\"},\n * {\"petOwner\":{\"Name\":\"Price\",\"Pets\":[\"Scratches\",\"Diesel\"]},\"petName\":\"Diesel\"},\n * {\"petOwner\":{\"Name\":\"Hines\",\"Pets\":[\"Dusty\"]},\"petName\":\"Dusty\"}\n * ]\n *\/\n\/\/ project the pet owner`s name and the pet`s name\nvar query = petOwners\n .SelectMany(petOwner => petOwner.Pets,\n (petOwner, petName) => new {petOwner, petName})\n .Where(ownerAndPet => ownerAndPet.petName.StartsWith(\"S\"))\n .Select(ownerAndPet => new {Owner = ownerAndPet.petOwner.Name,\n Pet = ownerAndPet.petName});\nforeach (var obj in query) {\n Console.WriteLine(obj);\n}<\/code><\/pre>\n\n\n\n41.SequenceEqual<\/h3>\n\n\n\nPet pet1 = new Pet{Name = \"Turbo\", Age = 2};\nPet pet2 = new Pet{Name = \"Peanut\", Age = 9};\n\nList<Pet> pets1 = new List<Pet>{pet1, pet2};\nList<Pet> pets2 = new List<Pet>{pet1, pet2};\n\nbool equal = pets1.SequenceEqual(pets2);\nConsole.WriteLine(\"The sequence is equals: {0}.\", equal); \/\/ True\n\nList<Pet> pets3 = new List<Pet>{pet1, pet2};\nList<Pet> pets4 = new List<Pet>{\n new Pet{Name = \"Turbo\", Age = 2},\n new Pet{Name = \"Peanut\", Age = 9},\n};\nbool equal2 = pets3.SequenceEqual(pets4);\nConsole.WriteLine(\"The sequence is equals: {0}.\", equal2); \/\/ False\n\/\/\u5728\u8fd9\u91cc\u6bd4\u8f83\u7684\u662f\u5f15\u7528\u5730\u5740\n\n\/\/\u53ef\u4ee5\u81ea\u884c\u5b9e\u73b0IEquatable\u63a5\u53e3\uff0c\u91cd\u5199GetHashCode\u548cEquals\u65b9\u6cd5\nList<ProductA> pets5 = new List<ProductA>{\n new ProductA{Name = \"Turbo\", Code = 2},\n new ProductA{Name = \"Peanut\", Code = 9},\n};\nList<ProductA> pets6 = new List<ProductA>{\n new ProductA{Name = \"Turbo\", Code = 2},\n new ProductA{Name = \"Peanut\", Code = 9},\n};\nbool equal3 = pets5.SequenceEqual(pets6);\nConsole.WriteLine(\"The sequence is equals: {0}.\", equal3); \/\/ True\n\nConsole.WriteLine(JsonConvert.SerializeObject((9, 9))); \/\/{\"Item1\":9,\"Item2\":9}<\/code><\/pre>\n\n\n\npublic class ProductA : IEquatable<ProductA> {\n public string Name {\n get;\n set;\n }\n public int Code {\n get;\n set;\n }\n\n public bool Equals(ProductA other) {\n if (other is null) return false;\n\n return this.Name == other.Name && this.Code == other.Code;\n }\n\n public override bool Equals(object obj) => Equals(obj as ProductA);\n public override int GetHashCode() =>(Name, Code).GetHashCode();\n}<\/code><\/pre>\n\n\n\n42.Single \u8fd4\u56de\u4e00\u6761\u5339\u914d\u7ed3\u679c<\/h3>\n\n\n\nstring[] fruits3 = {\"apple\", \"banana\", \"mango\",\n \"orange\", \"passionfruit\", \"grape\"};\nstring fruit1 = null;\ntry {\n fruit1 = fruits3.Single(fruit => fruit.Length > 20);\n} catch (System.InvalidOperationException) {\n Console.WriteLine(\n @\"The collection does not contain exactly one element whose length is grater than 20.\");\n}\nConsole.WriteLine(fruit1);<\/code><\/pre>\n\n\n\n43.SingleOrDefault<\/h3>\n\n\n\nstring[] fruits3 = {\"apple\", \"banana\", \"mango\",\n \"orange\", \"passionfruit\", \"grape\"};\nstring fruit1 = fruits3.SingleOrDefault(fruit => fruit.Length > 20);\nConsole.WriteLine(fruit1);<\/code><\/pre>\n\n\n\n44.Skip \u4ece\u5e8f\u53f70\u5f00\u59cb\u8df3\u8fc7\u6307\u5b9a\u4e2a<\/h3>\n\n\n\nint[] grades = {59, 82, 70, 56, 92, 98, 85};\nIEnumerable<int> lowerGrades = grades.OrderByDescending(g => g).Skip(3);\nConsole.WriteLine(\"All grades except the top three are:\");\nforeach (int grade in lowerGrades) {\n Console.WriteLine(grade);\n} \/*\n * All grades except the top three are:\n 82\n 70\n 59\n 56\n *\/<\/code><\/pre>\n\n\n\n45.SkipLast \u4ece\u672b\u5c3e\u5012\u6570\u8df3\u8fc7\u6307\u5b9a\u4e2a<\/h3>\n\n\n\nint[] grades = {59, 82, 70, 56, 92, 98, 85};\nIEnumerable<int> lowerGrades = grades.OrderByDescending(g => g).SkipLast(3);\nConsole.WriteLine(\"All grades except the last three are:\");\nforeach (int grade in lowerGrades) {\n Console.WriteLine(grade);\n} \/*\n *98\n 92\n 85\n 82\n *\/<\/code><\/pre>\n\n\n\n46.SkipWhile \u6309\u7279\u5b9a\u6761\u4ef6<\/h3>\n\n\n\nint[] grades = {59, 82, 70, 56, 92, 98, 85};\nIEnumerable<int> lowerGrades =\n grades.OrderByDescending(g => g).SkipWhile(g => g >= 80);\nConsole.WriteLine(\"All grades below 80:\");\nforeach (int grade in lowerGrades) {\n Console.WriteLine(grade);\n} \/*\n *All grades below 80:\n *70\n *59\n *56\n *\/<\/code><\/pre>\n\n\n\n47.Sum \u6c42\u548c<\/h3>\n\n\n\nint[] grades = { 59, 82, 70, 56, 92, 98, 85 };\nConsole.WriteLine(\"sum: {0}\", grades.Sum());\/\/sum: 542<\/code><\/pre>\n\n\n\n48.Take \u4ece\u5e8f\u53f70\u5f00\u59cb\u9009\u62e9\u6307\u5b9a\u4e2a<\/h3>\n\n\n\nint[] grades = {59, 82, 70, 56, 92, 98, 85};\nIEnumerable<int> lowerGrades = grades.OrderByDescending(g => g).Take(3);\nConsole.WriteLine(\"the top threee grades are:\");\nforeach (int grade in lowerGrades) {\n Console.WriteLine(grade);\n} \/*\n 98\n 92\n 85\n *\/<\/code><\/pre>\n\n\n\n49.TakeLast \u4ece\u672b\u5c3e\u5f00\u59cb\u5012\u6570\u9009\u62e9\u6307\u5b9a\u4e2a<\/h3>\n\n\n\nint[] grades = {59, 82, 70, 56, 92, 98, 85};\nIEnumerable<int> lowerGrades = grades.OrderByDescending(g => g).TakeLast(3);\nConsole.WriteLine(\"the last three grades are:\");\nforeach (int grade in lowerGrades) {\n Console.WriteLine(grade);\n}<\/code><\/pre>\n\n\n\n50.TakeWhile \u6309\u7279\u5b9a\u6761\u4ef6\u9009\u62e9<\/h3>\n\n\n\nint[] grades = {59, 82, 70, 56, 92, 98, 85};\nIEnumerable<int> lowerGrades =\n grades.OrderByDescending(g => g).TakeWhile(g => g >= 80);\nConsole.WriteLine(\"All grades grater than 80:\");\nforeach (int grade in lowerGrades) {\n Console.WriteLine(grade);\n}<\/code><\/pre>\n\n\n\n51.ThenBy \u540e\u7eed\u6392\u5e8f\uff0c\u7528\u4e8eOrderBy\u540e<\/h3>\n\n\n\nstring[] fruits3 = {\"grape\", \"passionfruit\", \"banana\", \"mango\",\n \"orange\", \"raspberry\", \"apple\", \"blueberry\"};\n\n\/\/ Sort the strings first by their length and then\n\/\/ alphabetically by passing the identity selector function.\nIEnumerable<string> query =\n fruits3.OrderBy(fruit => fruit.Length).ThenBy(fruit => fruit);\n\nforeach (string fruit in query) {\n Console.WriteLine(fruit);\n}\n\/*\n * apple\n * grape\n * mango\n * banana\n * orange\n * blueberry\n * raspberry\n * passionfruit\n *\/\n\/\/\u5f53\u6ca1\u6709\u4f7f\u7528ThenBy\u65f6\uff0c\u6ce8\u610f\u89c2\u5bdf\u5b57\u7b26\u957f\u5ea6\u4e00\u81f4\u7684\u6392\u5e8f\n\/* grape\n * mango\n * apple\n * banana\n * orange\n * raspberry\n * blueberry\n * passionfruit\n *\/<\/code><\/pre>\n\n\n\n52.ThenByDescending \u540e\u7eed\u6392\u5e8f\u5012\u5e8f<\/h3>\n\n\n\nstring[] fruits3 = {\"apPLe\", \"baNanA\", \"apple\", \"APple\",\n \"orange\", \"BAnana\", \"ORANGE\", \"apPLE\"};\n\n\/\/ Sort the strings first ascending by their length and\n\/\/ then descending using a custom case insensitive comparer.\nIEnumerable<string> query =\n fruits3.OrderBy(fruit => fruit.Length)\n .ThenByDescending(fruit => fruit, new CaseInsensitiveComparer());\nforeach (string fruit in query) {\n Console.WriteLine(fruit);\n}\n\/\/\u65e0ThenByDescending\u65f6\uff0c\u6ce8\u610f\u89c2\u5bdf\u957f\u5ea6\u4e00\u81f4\u7684\u5355\u8bcd\u6392\u5e8f\n\/*\n * apPLe\n * apple\n * APple\n * apPLE\n * baNanA\n * orange\n * BAnana\n * ORANGE\n *\/\n\/\/\u6709ThenByDescending\u65f6\uff0c\u6ce8\u610f\u89c2\u5bdf\u957f\u5ea6\u4e00\u81f4\u7684\u5355\u8bcd\u6392\u5e8f\n\/*\n * apPLe\n * apple\n * APple\n * apPLE\n * orange\n * ORANGE\n * baNanA\n * BAnana\n *\/<\/code><\/pre>\n\n\n\n53.ToArray<\/h3>\n\n\n\nList<Package> packages = new List<Package>{\n new Package{Company = \"Coho Vineyard\", Weight = 25.2},\n new Package{Company = \"Lucerne Publishing\", Weight = 18.7},\n new Package{Company = \"Wingtip Toys\", Weight = 6.0},\n new Package{Company = \"Adventure Works\", Weight = 33.8}};\n\nstring[] companies = packages.Select(pkg => pkg.Company).ToArray();\n\nforeach (string company in companies) {\n Console.WriteLine(company);\n}\n\/*\n *Coho Vineyard\n *Lucerne Publishing\n *Wingtip Toys\n *Adventure Works\n *\/<\/code><\/pre>\n\n\n\n54.ToDirectory<\/h3>\n\n\n\nList<Package> packages =\n new List<Package>{new Package{Company = \"Coho Vineyard\", Weight = 25.2,\n TrackingNumber = 89453312L},\n new Package{Company = \"Lucerne Publishing\",\n Weight = 18.7, TrackingNumber = 89112755L},\n new Package{Company = \"Wingtip Toys\", Weight = 6.0,\n TrackingNumber = 299456122L},\n new Package{Company = \"Adventure Works\", Weight = 33.8,\n TrackingNumber = 4665518773L}};\n\n\/\/ Create a Dictionary of Package objects,\n\/\/ using TrackingNumber as the key.\nDictionary<long, Package> dictionary =\n packages.ToDictionary(p => p.TrackingNumber);\n\nforeach (KeyValuePair<long, Package> kvp in dictionary) {\n Console.WriteLine(\"Key {0}: {1}, {2} pounds\", kvp.Key, kvp.Value.Company,\n kvp.Value.Weight);\n}<\/code><\/pre>\n\n\n\nclass Package {\n public string Company {\n get;\n set;\n }\n public double Weight {\n get;\n set;\n }\n public long TrackingNumber {\n get;\n set;\n }\n}<\/code><\/pre>\n\n\n\n55.ToHashSet<\/h3>\n\n\n\npublic class ProductA : IEquatable<ProductA> {\n public string Name {\n get;\n set;\n }\n public int Code {\n get;\n set;\n }\n\n public bool Equals(ProductA other) {\n if (other is null) return false;\n\n return this.Name == other.Name && this.Code == other.Code;\n }\n\n public override bool Equals(object obj) => Equals(obj as ProductA);\n public override int GetHashCode() =>(Name, Code).GetHashCode();\n}\n<\/code><\/pre>\n\n\n\npublic class ProductB {\n public string Name {\n get;\n set;\n }\n public int Code {\n get;\n set;\n }\n}<\/code><\/pre>\n\n\n\nint[] a = new int[]{1, 2, 3, 4, 5, 4, 3, 2, 1};\nConsole.WriteLine(JsonConvert.SerializeObject(a.ToHashSet())); \/\/[1,2,3,4,5]\nList<ProductA> pets5 = new List<ProductA>{\n new ProductA{Name = \"Peanut\", Code = 9},\n new ProductA{Name = \"Turbo\", Code = 2},\n new ProductA{Name = \"Peanut\", Code = 9},\n};\nConsole.WriteLine(JsonConvert.SerializeObject(\n pets5\n .ToHashSet())); \/\/[{\"Name\":\"Peanut\",\"Code\":9},{\"Name\":\"Turbo\",\"Code\":2}]\nList<ProductB> pets6 = new List<ProductA2>{\n new ProductB{Name = \"Peanut\", Code = 9},\n new ProductB{Name = \"Turbo\", Code = 2},\n new ProductB{Name = \"Peanut\", Code = 9},\n};\nConsole.WriteLine(JsonConvert.SerializeObject(pets6.ToHashSet(\n new ProductBComparer()))); \/\/[{\"Name\":\"Peanut\",\"Code\":9},{\"Name\":\"Turbo\",\"Code\":2}]<\/code><\/pre>\n\n\n\npublic class ProductBComparer : IEqualityComparer<Product> {\n bool IEqualityComparer<ProductB>.Equals(ProductB? x, ProductB? y) {\n if (x is null || y is null) return false;\n\n return x.Name == y.Name && x.Code == y.Code;\n }\n\n int IEqualityComparer<ProductB>.GetHashCode(ProductB obj) {\n return (obj.Name, obj.Code).GetHashCode();\n }\n}<\/code><\/pre>\n\n\n\n56.ToList<\/h3>\n\n\n\nint[] a = new int[]{1, 2, 3, 4, 5, 4, 3, 2, 1};\nConsole.WriteLine(\n JsonConvert.SerializeObject(a.ToList())); \/\/[1,2,3,4,5,4,3,2,1]<\/code><\/pre>\n\n\n\n57.ToLookup \u5206\u7ec4<\/h3>\n\n\n\nclass PackageB {\n public string Company {\n get;\n set;\n }\n public double Weight {\n get;\n set;\n }\n public long TrackingNumber {\n get;\n set;\n }\n}<\/code><\/pre>\n\n\n\n\/\/ Create a list of Packages.\nList<PackageB> packages = new List<PackageB>{\n new PackageB{Company = \"Coho Vineyard\", Weight = 25.2,\n TrackingNumber = 89453312L},\n new PackageB{Company = \"Lucerne Publishing\", Weight = 18.7,\n TrackingNumber = 89112755L},\n new PackageB{Company = \"Wingtip Toys\", Weight = 6.0,\n TrackingNumber = 299456122L},\n new PackageB{Company = \"Contoso Pharmaceuticals\", Weight = 9.3,\n TrackingNumber = 670053128L},\n new PackageB{Company = \"Wide World Importers\", Weight = 33.8,\n TrackingNumber = 4665518773L}};\n\n\/\/ Create a Lookup to organize the packages.\n\/\/ Use the first character of Company as the key value.\n\/\/ Select Company appended to TrackingNumber\n\/\/ as the element values of the Lookup.\nILookup<char, string> lookup = packages.ToLookup(\n p => p.Company[0], p => p.Company + \" \" + p.TrackingNumber);\n\n\/\/ Iterate through each IGrouping in the Lookup.\nforeach (IGrouping<char, string> packageGroup in lookup) {\n \/\/ Print the key value of the IGrouping.\n Console.WriteLine(packageGroup.Key);\n \/\/ Iterate through each value in the\n \/\/ IGrouping and print its value.\n foreach (string str in packageGroup) Console.WriteLine(\" {0}\", str);\n}\n\/*\n *\nC\nCoho Vineyard 89453312\nContoso Pharmaceuticals 670053128\nL\nLucerne Publishing 89112755\nW\nWingtip Toys 299456122\nWide World Importers 4665518773*\/<\/code><\/pre>\n\n\n\n58.TryGetNonEnumeratedCount \u5c1d\u8bd5\u5728\u4e0d\u679a\u4e3e\u7684\u60c5\u51b5\u4e0b\u83b7\u53d6\u5e8f\u5217\u4e2d\u5143\u7d20\u6570\u91cf<\/h3>\n\n\n\nint[] a = new int[]{1, 2, 3, 4, 5, 4, 3, 2, 1};\na.TryGetNonEnumeratedCount(out int theCount);\nConsole.WriteLine(theCount); \/\/ 9<\/code><\/pre>\n\n\n\n59.Union \u8054\u5408\uff08\u4f1a\u53bb\u91cd\uff09<\/h3>\n\n\n\npublic class ProductA : IEquatable<ProductA> {\n public string Name {\n get;\n set;\n }\n public int Code {\n get;\n set;\n }\n\n public bool Equals(ProductA other) {\n if (other is null) return false;\n\n return this.Name == other.Name && this.Code == other.Code;\n }\n\n public override bool Equals(object obj) => Equals(obj as ProductA);\n public override int GetHashCode() =>(Name, Code).GetHashCode();\n}<\/code><\/pre>\n\n\n\nint[] ints1 = {5, 3, 9, 7, 5, 9, 3, 7};\nint[] ints2 = {8, 3, 6, 4, 4, 9, 1, 0};\n\nIEnumerable<int> union\n= ints1.Union(ints2);\n\nforeach (int num in union) {\n Console.Write(\"{0} \", num); \/\/ 5 3 9 7 8 6 4 1 0\n}\nConsole.WriteLine();\n\nProductA[] store1 = {new ProductA{Name = \"apple\", Code = 9},\n new ProductA{Name = \"orange\", Code = 4}};\n\nProductA[] store2 = {new ProductA{Name = \"apple\", Code = 9},\n new ProductA{Name = \"lemon\", Code = 12}};\nIEnumerable<ProductA> union2 = store1.Union(store2);\nConsole.WriteLine(JsonConvert.SerializeObject(\n union2)); \/\/[{\"Name\":\"apple\",\"Code\":9},{\"Name\":\"orange\",\"Code\":4},{\"Name\":\"lemon\",\"Code\":12}]<\/code><\/pre>\n\n\n\n60.UnionBy \u5c06\u51fd\u6570\u5904\u7406\u540e\u7684\u7ed3\u679c\u8054\u5408<\/h3>\n\n\n\nvar a = new[]{1, 2, 3, 4, 5, 6, 7};\nvar b = new[]{4, 5, 6, 7, 8, 9, 10};\nFunc<int, string> transform = i => i.ToString();\n\nvar result = a.UnionBy(b, transform);\n\nConsole.WriteLine(JsonConvert.SerializeObject(\n result)); \/\/\"1\", \"2\", \"3\", \"4\", \"5\", \"6\", \"7\", \"8\", \"9\", \"10\"<\/code><\/pre>\n\n\n\n61.Where<\/h3>\n\n\n\nList<string> fruits2 =\n new List<string>{\"apple\", \"passionfruit\", \"banana\", \"mango\",\n \"orange\", \"blueberry\", \"grape\", \"strawberry\"};\n\nIEnumerable<string> query = fruits2.Where(fruit => fruit.Length < 6);\n\nforeach (string fruit in query) {\n Console.WriteLine(fruit);\n}\n\/\/ apple mango grape<\/code><\/pre>\n\n\n\n62.Zip \u7ed3\u5408\u4e24\u4e2a\u96c6\u5408<\/h3>\n\n\n\nint[] numbers = {1, 2, 3, 4};\nstring[] words = {\"one\", \"two\", \"three\"};\n\nvar numbersAndWords =\n numbers.Zip(words, (first, second) => first + \" \" + second);\n\nforeach (var item in numbersAndWords) Console.WriteLine(item);\n\/*\n * 1 one\n * 2 two\n * 3 three\n *\/<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"\u63d0\u4f9b\u4e00\u7ec4\u9759\u6001\u65b9\u6cd5\u7528\u4e8e\u67e5\u8be2\u5b9e\u73b0IEnumerable<T>\u7684\u5bf9\u8c61\u3002 Methods 1.Aggreg […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[19],"tags":[26],"_links":{"self":[{"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/posts\/320"}],"collection":[{"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=320"}],"version-history":[{"count":10,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/posts\/320\/revisions"}],"predecessor-version":[{"id":332,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/posts\/320\/revisions\/332"}],"wp:attachment":[{"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=320"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=320"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=320"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}