本文概述
- LINQ GroupBy()方法的语法
- 方法语法中的LINQ GroupBy()的示例
- 查询语法中的LINQ GroupBy()示例
LINQ GroupBy()方法的语法 这是使用LINQ GroupBy()方法根据键的指定值对元素进行分组的语法。
var student1 = objStudent.GroupBy(x =>
x.Location);
通过以上语法, 我们将根据学生的位置对集合的” objStudent” 项进行分组。
方法语法中的LINQ GroupBy()的示例 这是在方法语法中使用LINQ GroupBy()的示例。
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleApp1{class Programme2{static void Main(string[] args){//Create an object 'objStudent' of the list of the studentList<
Student>
objStudent = new List<
Student>
(){new Student() { Name = "Ak Tyagi", Gender = "Male", Location="Chennai" }, new Student() { Name = "Rohini", Gender = "Female", Location="Chennai" }, new Student() { Name = "Praveen", Gender = "Male", Location="Bangalore" }, new Student() { Name = "Sateesh", Gender = "Male", Location ="Vizag"}, new Student() { Name = "Madhav", Gender = "Male", Location="Nagpur"}};
// here with the help of GrouBy we will fetch the student on the base of locationvar student1 = objStudent.GroupBy(x =>
x.Location);
foreach (var sitem in student1){// WriteLine() function here count the number of studentConsole.WriteLine(sitem.Key, sitem.Count());
Console.WriteLine();
foreach (var stud in sitem){//Console.WriteLine(stud.Name + "\t" + stud.Location) show the information of the student on the base of the locationConsole.WriteLine(stud.Name + "\t" + stud.Location);
}Console.WriteLine();
}Console.ReadLine();
}}//Student class containing the name of the student, gender and location of the studentclass Student{public string Name { get;
set;
}public string Gender { get;
set;
}public string Location { get;
set;
}}}在上面的示例中, 我们根据学生的位置将” objStudent” 中的项目集合分组。
输出
文章图片
查询语法中的LINQ GroupBy()示例 这是使用LINQ GroupBy()运算符的示例。
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleApp1{class Programme2{static void Main(string[] args){//create an object objStudent of the Student List and add some informationList<
Student>
objStudent = new List<
Student>
(){new Student() { Name = "Vinay Tyagi", Gender = "Male", Location="Chennai" }, new Student() { Name = "Rohini", Gender = "Female", Location="Chennai" }, new Student() { Name = "Praveen", Gender = "Male", Location="Bangalore" }, new Student() { Name = "Sateesh Alavala", Gender = "Male", Location ="Vizag"}, new Student() { Name = "Madhav Sai", Gender = "Male", Location="Nagpur"}};
//apply the linq queries to group the information of the student according to the location/*linq queries starts from, from take a variable 'std' in objStudent(object of the Student List) group 'std'(declared variable) by std.Location*/var student = from std in objStudentgroup std by std.Location;
//foreach loop iterate over all the information of the studentforeach (var sitem in student){Console.WriteLine(sitem.Key, sitem.Count());
Console.WriteLine();
foreach (var stud in sitem){/*Console.WriteLine(stud.Name + "\t" + stud.Location) show the information of the student on the base of the location*/Console.WriteLine(stud.Name + "\t" + stud.Location);
}Console.WriteLine();
}Console.ReadLine();
}}class Student{public string Name { get;
set;
}public string Gender { get;
set;
}public string Location { get;
set;
}}}输出
文章图片
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