[c#] Getting the index of a particular item in array

I want to retrieve the index of an array but I know only a part of the actual value in the array.

For example, I am storing an author name in the array dynamically say "author = 'xyz'".
Now I want to find the index of the array item containing it, since I don't know the value part.

How to do this?

     int i=  Array.IndexOf(temp1,  temp1.Where(x=>x.Contains("abc")).FirstOrDefault());

try Array.FindIndex(myArray, x => x.Contains("author"));

FindIndex Extension

static class ArrayExtensions
{
    public static int FindIndex<T>(this T[] array, Predicate<T> match)
    {
        return Array.FindIndex(array, match);
    }
}

Usage

int[] array = { 9,8,7,6,5 };

var index = array.FindIndex(i => i == 7);

Console.WriteLine(index); // Prints "2"

Here's a fiddle with it.

Bonus: IndexOf Extension

I wrote this first not reading the question properly...

static class ArrayExtensions
{
    public static int IndexOf<T>(this T[] array, T value)
    {
        return Array.IndexOf(array, value);
    }   
}

Usage

int[] array = { 9,8,7,6,5 };

var index = array.IndexOf(7);

Console.WriteLine(index); // Prints "2"

Here's a fiddle with it.

The previous answers will only work if you know the exact value you are searching for - the question states that only a partial value is known.

Array.FindIndex(authors, author => author.Contains("xyz"));

This will return the index of the first item containing "xyz".