Here's how:

if(stringArray.Any(stringToCheck.Contains))

This checks if stringToCheck contains any one of substrings from stringArray. If you want to ensure that it contains all the substrings, change Any to All:

if(stringArray.All(s => stringToCheck.Contains(s)))

Try this:

No need to use LINQ

if (Array.IndexOf(array, Value) >= 0)
{
    //Your stuff goes here
}

Using Linq and method group would be the quickest and more compact way of doing this.

var arrayA = new[] {"element1", "element2"};
var arrayB = new[] {"element2", "element3"};
if (arrayB.Any(arrayA.Contains)) return true;

Something like this perhaps:

string stringToCheck = "text1text2text3";
string[] stringArray = new string[] { "text1" };
if (Array.Exists<string>(stringArray, (Predicate<string>)delegate(string s) { 
    return stringToCheck.IndexOf(s, StringComparison.OrdinalIgnoreCase) > -1; })) {
    Console.WriteLine("Found!");
}

I use the following in a console application to check for arguments

var sendmail = args.Any( o => o.ToLower() == "/sendmail=true");

try this, here the example : To check if the field contains any of the words in the array. To check if the field(someField) contains any of the words in the array.

String[] val = { "helloword1", "orange", "grape", "pear" };   

Expression<Func<Item, bool>> someFieldFilter = i => true;

someFieldFilter = i => val.Any(s => i.someField.Contains(s));

Try:

String[] val = { "helloword1", "orange", "grape", "pear" };
String sep = "";
string stringToCheck = "word1";

bool match = String.Join(sep,val).Contains(stringToCheck);
bool anothermatch = val.Any(s => s.Contains(stringToCheck));

string [] lines = {"text1", "text2", "etc"};

bool bFound = lines.Any(x => x == "Your string to be searched");

bFound sets to true if searched string is matched with any element of array 'lines'.

I used the following code to check if the string contained any of the items in the string array:

foreach (string s in stringArray)
{
    if (s != "")
    {
        if (stringToCheck.Contains(s))
        {
            Text = "matched";
        }
    }
}

You can also do the same thing as Anton Gogolev suggests to check if any item in stringArray1 matches any item in stringArray2:

if(stringArray1.Any(stringArray2.Contains))

And likewise all items in stringArray1 match all items in stringArray2:

if(stringArray1.All(stringArray2.Contains))

public bool ContainAnyOf(string word, string[] array) 
    {
        for (int i = 0; i < array.Length; i++)
        {
            if (word.Contains(array[i]))
            {
                return true;
            }
        }
        return false;
    }

I used a similar method to the IndexOf by Maitrey684 and the foreach loop of Theomax to create this. (Note: the first 3 "string" lines are just an example of how you could create an array and get it into the proper format).

If you want to compare 2 arrays, they will be semi-colon delimited, but the last value won't have one after it. If you append a semi-colon to the string form of the array (i.e. a;b;c becomes a;b;c;), you can match using "x;" no matter what position it is in:

bool found = false;
string someString = "a-b-c";
string[] arrString = someString.Split('-');
string myStringArray = arrString.ToString() + ";";

foreach (string s in otherArray)
{
    if (myStringArray.IndexOf(s + ";") != -1) {
       found = true;
       break;
    }
}

if (found == true) { 
    // ....
}