Conditionally Split a List in C#

This post will discuss how to conditionally split a list in C#.

We can use the Enumerable.GroupBy() method to conditionally group the elements based on some condition. For example, the following code split a list into sublists based on odd-even values:

using System;

using System.Linq;

using System.Collections.Generic;

public class Example

{

public static void Main()

{

List<int> nums = new List<int>() { 1, 2, 3, 4, 5 };

// split list into odd-even

var partitions = nums.GroupBy(x => x % 2 == 0);

foreach (var partition in partitions) {

Console.WriteLine(String.Join(", ", partition));

}

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Output:

1, 3, 5
2, 4

The GroupBy() method can also be used to conditionally split the list based on a certain property. The following code example shows how to split a list of students into sublists based on their age:

using System;

using System.Linq;

using System.Collections.Generic;

class Student

{

public string name { get; set; }

public decimal age { get; set; }

public override string ToString() {

return "[" + name + ", " + age + "]";

}

public class Example

{

public static void Main()

{

List<Student> values = new List<Student>

{

new Student{name = "Olivia", age = 10},

new Student{name = "Robert", age = 20},

new Student{name = "John", age = 15}

};

// split list based on age

var partitions = values.GroupBy(x => x.age >= 18);

foreach (var partition in partitions) {

Console.WriteLine(String.Join(", ", partition));

}

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Output:

[Olivia, 10], [John, 15]
[Robert, 20]

That’s all about conditionally splitting a list in C#.

Conditionally Split a List in C#

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