How to Remove Element from List based on a Condition in C# - Step by Step Examples

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How to Remove Element from List based on a Condition in C# ?

Answer

To remove elements from a list in C# using `System.Collections.Generic.List`, you can use the `RemoveAll` method.

✐ Examples

1 Remove Elements Greater Than a Threshold

In this example,

We include the necessary namespaces for using List.
We create a list named numbers with some elements.
We specify the threshold value.
We use the RemoveAll method along with a lambda function to remove elements greater than the threshold.
Finally, we print the modified list to standard output.

C# Program

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        List<int> numbers = new List<int> { 1, 2, 3, 4, 5 };
        int threshold = 3;
        numbers.RemoveAll(x => x > threshold);
        foreach (var num in numbers)
        {
            Console.Write(num + " ");
        }
    }
}

Output

1 2 3

2 Remove Elements Matching a Predicate

In this example,

We include the necessary namespaces for using List.
We create a list named names with some elements.
We define a predicate function IsLongName that returns true if the length of the string is greater than a specified value.
We use the RemoveAll method along with the IsLongName predicate to remove elements matching the predicate condition.
Finally, we print the modified list to standard output.

C# Program

using System;
using System.Collections.Generic;

class Program
{
    static bool IsLongName(string name, int maxLength)
    {
        return name.Length > maxLength;
    }

    static void Main()
    {
        List<string> names = new List<string> { "John", "Alice", "Michael", "Emma" };
        int maxLength = 5;
        names.RemoveAll(name => IsLongName(name, maxLength));
        foreach (var name in names)
        {
            Console.Write(name + " ");
        }
    }
}

Output

John Alice Emma

Summary

In this tutorial, we learned How to Remove Element from List based on a Condition in C# language with well detailed examples.

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How to Remove Element from List based on a Condition in C# - Step by Step Examples

How to Remove Element from List based on a Condition in C# ?

Answer

✐ Examples

1 Remove Elements Greater Than a Threshold

C# Program

Output

2 Remove Elements Matching a Predicate

C# Program

Output

Summary

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