Provides a helper method for determining weather two value ranges intersect.

LINQPad v4 C# sample RangeIntersection.linq (5.18 kb)

/// <summary>
/// Check for the intersection between two sets of ranges.
/// </summary>
/// <param name="range1Start">The start of the first range.</param>
/// <param name="range1End">The end of the first reage.</param>
/// <param name="range2Start">The start of the second range.</param>
/// <param name="range2End">The end of the second range.</param>
/// <returns>true if the two ranges intersect with each other; otherwise false.</returns>
public static bool RangeIntersection(int range1Start, int range1End, int range2Start, int range2End)
{
    var r1Start = range1Start;
    var r1End = range1End;
    var r2Start = range2Start;
    var r2End = range2End;

    if (range1Start > range1End)
    {
        r1Start = range1End;
        r1End = range1Start;
    }

    if (range2Start > range2End)
    {
        r2Start = range2End;
        r2End = range2Start;
    }

    var greatestStart = r1Start > r2Start ? r1Start : r2Start;
    var smallestEnd = r1End < r2End ? r1End : r2End;
    return !(greatestStart > smallestEnd);
}