Binary Search in C#

When the records you are searching through are sorted into order, you can perform a more efficient search than the sequential search to find a value. This search is called a binary search.
To use this search first we need to sort our data in ascending order.

C# Function for Binary Search

int BinarySearchMethod(int value, int[]arr)

        {

            int lower = 0;

            int upper = arr.Length - 1;

            while (lower <= upper)

            {

                int mid = (lower + upper) / 2;

                if (value == arr[mid])

                {

                    return mid;

                }

                else if (value > arr[mid])

                {

                    lower = mid + 1;

                }

                else

                {

                    upper = mid - 1;

                }

            }

            return -1;

        }

If value is found in Array then this above function will return the 'position' of element.