string [] arr = {"One","Two","Three"};
var target = "One";
var results = Array.FindAll(arr, s => s.Equals(target));
OR
string stringToCheck = "text1";
string[] stringArray = { "text1", "testtest", "test1test2", "test2text1" };
foreach (string x in stringArray)
{
if (x.Contains(stringToCheck))
{
}
}
Give it a try.This may help.If not ask here.