How can I check if a string contains a character in C#?

Question

Is there a function I can apply to a string that will return true of false if a string contains a character.

I have strings with one or more character options such

Answer 1

here is an example what most of have done

using System;

class Program
{
    static void Main()
    {
        Test("Dot Net Perls");
        Test("dot net perls");
    }

    static void Test(string input)
    {
        Console.Write("--- ");
        Console.Write(input);
        Console.WriteLine(" ---");
        //
        // See if the string contains 'Net'
        //
        bool contains = input.Contains("Net");
        //
        // Write the result
        //
        Console.Write("Contains 'Net': ");
        Console.WriteLine(contains);
        //
        // See if the string contains 'perls' lowercase
        //
        if (input.Contains("perls"))
        {
            Console.WriteLine("Contains 'perls'");
        }
        //
        // See if the string contains 'Dot'
        //
        if (!input.Contains("Dot"))
        {
            Console.WriteLine("Doesn't Contain 'Dot'");
        }
    }
}

Answer 2

The following should work:

var abc = "sAb";
bool exists = abc.IndexOf("ab", StringComparison.CurrentCultureIgnoreCase) > -1;