As others have said, a Dictionary<string, string> would be better - and you can use a collection initializer to create it simply:
Dictionary<string, string> dictionary = new Dictionary<string, string>
{
{"ant", "AUNT_ID"},
{"Sam", "AUNT_NAME"},
{"clozapine", "OPTION"},
};
If you're confident that your key is in the dictionary, and you're happy for an exception to be thrown otherwise:
string value = dictionary[key];
or if it might not be:
string value;
if (dictionary.TryGetValue(key, out value))
{
// Use value here
}
else
{
// Key wasn't in dictionary
}
If you really need to use an array, if you can change it to a multidimensional array (string[][]), you can use:
// Will throw if there are no matches
var value = array.First(x => x[0] == key)[1];
Or again to be more circumspect:
var pair = array.FirstOrDefault(x => x[0] == key);
if (pair != null)
{
string value = pair[1];
// Use value here
}
else
{
// Key wasn't in dictionary
}
LINQ unfortunately doesn't work quite as well on rectangular arrays. It probably wouldn't be too hard to write a method to allow it to be treated "somewhat" like an array of arrays, admittedly...