C# - Checking if strings have this

Question

how can I Check if a string contains another string?

Answer 1

    public bool HasString(string item, List<string> arrayOfStrings)
    {
        return arrayOfStrings.Contains(item);
    }

Answer 2

string lookup = "test";
bool hasString = array.Contains(lookup);

Answer 3

Why iterate when you can use LINQ? I think you're asking to get all the strings that are substrings of other strings in the array (please correct me if I'm wrong):

var result = strings.Where(s => strings.Any(s2 => s2.Contains(s)));

Update

After your update, the question seems much easier than original. If you just want to find out if a string contains another string, just use the Contains method:

var s = "Hello World!";
var subString = "Hello";

var isContained = s.Contains(subString);

Or if you want to do a case insensitive search, you have to do things a little differently:

var s = "Hello World!";
var subString = "hello";

var isContained = s.IndexOf(subString, 
    StringComparison.InvariantCultureIgnoreCase) > 0;

Answer 4

IEnumerable<string> values = new[] { "" };
string searchTarget = "";
string firstMatch = values.FirstOrDefault(s => s.Contains(searchTarget);
if(firstMatch != null)
{
    // ...
}

Answer 5

You can use the method named IndexOf.

string s1 = "abcd";
string s2 = "cd";
if(s1.IndexOf(s2)>-1) {
   // if s2 is found in s1
}

Answer 6

The way I'm reading it you're asking if a big string contains another, shorter string?

string bigString = "something";
string testString = "s";
bool containsTestString = bigString.IndexOf(testString) > -1;