how to use C# contain code example

Example 1: c# string contains

bool b = s1.Contains("myString");

Example 2: check if string is in string[] c#

string stringToCheck = "text1";
string[] stringArray = { "text1", "testtest", "test1test2", "test2text1" };
foreach (string x in stringArray)
{
    if (x == stringToCheck)
    {
        // Process...
    }
}