使用 LINQ 打印姓名以“S”开头且年龄大于 23 的员工的 C# 程序

LINQ 被称为语言集成查询，它是在 .NET 3.5 中引入的。它使 .NET 语言能够生成查询以从数据源中检索数据。它消除了编程语言和数据库之间的不匹配，并且无论使用哪种类型的数据源，用于创建查询的语法都是相同的。在本文中，我们将学习如何使用 LINQ 打印姓名以“S”开头且年龄大于 23 岁的员工的详细信息。

例子：

Input : List of Employees:
         {{id = 101, name = "Sravan", age = 32},
          {id = 102, name = "deepu",  age = 15},
          {id = 103, name = "manoja", age = 13},
          {id = 104, name = "Sathwik", age = 12},
          {id = 105, name = "Saran",  age = 25}}
Output : {{id = 105, name = "sravan", age = 32},
          {id = 105, name = "Saran",  age = 25}}
 
Input : List of Employees:
        {{id = 102, name = "deepu",  age = 15},
         {id = 103, name = "manoja", age = 13}}
Output : No Output

方法：

To find the list of employees whose name starts with ‘S’ and their age is greater than 23 follow the following steps:

Create a list of employees with four variables(Id, name, department, and age).
Iterate through the employee details by using where clause and get the employee details by choosing employee name starts with’ S’ and their age is greater than 23. So, we write where emp.Name[0] == ‘S’ && emp.Age > 23 .
Now call the ToString() method.
Display the employee details.

编程需要懂一点英语

例子：

C#

// C# program to display the details of 
// those employees whose name is starts 
// with S and their age is greater than 23
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
  
class Employee{
      
// Declare four variables - id, age, department, and name
int id; 
int age;
string department;
string name;
  
// Get the to string method that returns 
// id, age, department, and name
public override string ToString()
{
    return id + " " + name + " " + age + " " + department;
}
  
// Driver code
static void Main(string[] args)
{
      
    // Declare a list variable 
    List emp = new List()
    {
          
        // Create 5 Employee details
        new Employee{ id = 101, name = "Sravan",  
                      age = 32, department = "HR" },
        new Employee{ id = 102, name = "deepu", 
                      age = 15, department = "Development" },
        new Employee{ id = 103, name = "manoja", 
                      age = 13, department = "Development" },
        new Employee{ id = 104, name = "Sathwik", 
                      age = 12, department = "HR" },
        new Employee{ id = 105, name = "Saran", 
                      age = 25, department = "Designing" }
    };
      
    // Iterate the Employee by selecting Employee 
    // name starts with S and age is greater than 23
    IEnumerable result = from e in emp 
                                   where e.name[0] == 'S' && e.age > 23 
                                   select e;
      
    // Display employee details
    Console.WriteLine("ID  Name  Age Department");
    Console.WriteLine("+++++++++++++++++++++++++");
    foreach (Employee x in result)
    {
          
        // Call the to string method
        Console.WriteLine(x.ToString());
    }    
}
}

输出：

ID  Name  Age Department
+++++++++++++++++++++++++
101 Sravan 32 HR
105 Saran 25 Designing