C# Excel Function - unreachable code detected

Question

I'm attempting to create a function class in C# for use in an excel Automation add-in. Using the simple code below, I was wanting to add the values in a range that match the colour that the user selects (for example, sum Range("A1:A10") where the cell colour is the same as "B1" would be: colourSum(A1:A10,B1).

    public double ColourSum(Range RangeToSum, Range cellContainingColourToSum)
    {
        double currentTotal = 0;
        //return 0; this code is edited from my original posting, due to posting error
        for (int i = 0; i < RangeToSum.Cells.Count;i++) //error at 'int i'
        {
            double iColour = RangeToSum.Interior.ColorIndex(i);
            if (iColour == cellContainingColourToSum.Interior.ColorIndex)
            {
                currentTotal = currentTotal + RangeToSum.Value2(i);
                //return currentTotal;

            }

        }
        return currentTotal;
    }

Unfortunately, the above code returns "Unreachable code detected" on line 4. The code example I've given is a simplified example of what I actually want to do but illustrates my point quite well. Is there a problem with my code, or can I write in a better way to avoid this problem?

Thanks, Rico.

To conclude the question, the following code worked completely (changing for(int i...with foreach (Range r...):

    public double ColourSum(Range RangeToSum, Range cellContainingColourToSum)
    {
        double currentTotal = 0;
        foreach (Range r in RangeToSum)
        {
            double iColour = r.Interior.ColorIndex;
            if (iColour == cellContainingColourToSum.Interior.ColorIndex)
            {
                currentTotal = currentTotal + r.Value2;
            }
        }
        return currentTotal;
    }

Answer 1

The minute your code hits the line:

return 0;

it will exit, there's no way for it to reach the rest of the code. Remove the line.

Answer 2

When the line return 0 is hit, the function ends, and nothing after that is executed. Hence, it is unreachable code. Remove this line to get the function to behave properly.