C# String Array Contains Multiple Values [Methods & Examples]

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c# string array contains multiple values

In this C# tutorial, I have explained, how to check if a C# string array contains multiple values with various methods and examples.

C# String Array Contains Multiple Values

A string array is an array that holds a collection of strings. Often, developers need to check if a string array contains one or more specific string values. In this complete tutorial, we’ll go over various ways to check if a C# string array contains multiple values.

Basic Approach: Using Array.Contains()

The most straightforward way to check if a string array contains a single value is by using the static method Array.Contains() from the System namespace in C#.

Here’s a basic example:

using System;

namespace StringArrayDemo
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] usaNames = { "Alice", "Bob", "Charlie", "David" };
            string nameToCheck = "Charlie";
            
            if (Array.Exists(usaNames, element => element == nameToCheck))
            {
                Console.WriteLine($"{nameToCheck} is in the array.");
            }
            else
            {
                Console.WriteLine($"{nameToCheck} is not in the array.");
            }
        }
    }
}

In this example, we used the Array.Exists() method to check if the string “Charlie” exists in the string array usaNames.

Once you run the code using Visual Studio, you can see the output below:

c# string array contains multiple values

Checking Multiple Values

To extend this to multiple values, you could loop through the list of values you want to check and call Array.Contains() for each one.

Here’s an example:

using System;

namespace StringArrayDemo
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] usaNames = { "Alice", "Bob", "Charlie", "David" };
            string[] namesToCheck = { "Alice", "Emily", "David" };
            
            foreach (var name in namesToCheck)
            {
                if (Array.Exists(usaNames, element => element == name))
                {
                    Console.WriteLine($"{name} is in the array.");
                }
                else
                {
                    Console.WriteLine($"{name} is not in the array.");
                }
            }
        }
    }
}

Once you run the code using Visual Studio, you can check the output like the below screenshot.

Check if c# string array contains multiple values

Using LINQ for More Elegance

If you are familiar with LINQ (Language-Integrated Query), you can use it to make your code shorter and more readable.

Here’s how you can check if all the specified values are in the array in C#:

using System;
using System.Linq;

namespace StringArrayDemo
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] usaNames = { "Alice", "Bob", "Charlie", "David" };
            string[] namesToCheck = { "Alice", "Emily", "David" };
            
            bool allExist = namesToCheck.All(name => usaNames.Contains(name));
            
            if (allExist)
            {
                Console.WriteLine("All names are in the array.");
            }
            else
            {
                Console.WriteLine("Not all names are in the array.");
            }
        }
    }
}

You can also check if any of the specified values exist in the array:

bool anyExist = namesToCheck.Any(name => usaNames.Contains(name));

if (anyExist)
{
    Console.WriteLine("At least one name is in the array.");
}
else
{
    Console.WriteLine("None of the names are in the array.");
}

Case Sensitivity

By default, the string comparison in C# is case-sensitive. To perform a case-insensitive check, you can specify the StringComparer.OrdinalIgnoreCase in the Contains method when using LINQ.

bool allExist = namesToCheck.All(name => usaNames.Contains(name, StringComparer.OrdinalIgnoreCase));

Summary

Checking if a string array contains one or more values is a common requirement in C# programming. While you can use basic loops and conditional statements to accomplish this, utilizing built-in methods like Array.Exists() or LINQ queries can make your code more concise and readable. I hope you got an idea of how to check if a c# string array contains multiple values.

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