Draw 2 adjacent rectangles using ASCII characters

Question

My objective is to draw 2 rectangles adjacent to each other. I wrote the code for drawing a rectangle but I could not draw 2 adjacent rectangles. I see where to problem is but I am not sure how to fix it. Help is greatly appreciated.

class DrawRectangles
{           
    static void Main(){
        Console.WriteLine(DrawRectangle(8,8)+DrawRectangle(4,3));
    }
    static string DrawRectangle(int width,int length){
        StringBuilder sb = new StringBuilder();
        string first = "+" + " -".StringMultiplier(width-1)+ " + ";
        sb.AppendLine(first);
        for(int i=0; i<length-1;i++)
            sb.AppendLine("|"+" ".StringMultiplier(2*width-1)+"|");
        sb.Append(first);
        return sb.ToString();
    }
}   

internal static class StringExtensions
{       
    public static string StringMultiplier(this string value,int count){
        StringBuilder sb = new StringBuilder(count);
        for(int i=0;i<count;i++)
            sb.Append(value);
        return sb.ToString();
    }       
}

Expected output:

+ - - - - - - - + 
|               |
|               |
|               |
|               |+ - - - +
|               ||       |
|               ||       |
|               ||       |
+ - - - - - - - ++ - - - + 

Current output:

+ - - - - - - - + 
|               |
|               |
|               |
|               |
|               |
|               |
|               |
+ - - - - - - - ++ - - - + 
|       |
|       |
+ - - - +

Answer 1

Firstly, the StringMultiplier extension is unnecessary because you can use System.String(Char, Int32) to accomplish the same thing.

Here's the code you'll actually need:

// Assume the Tuples are <height, width>
string DrawRectangles(params Tuple<int, int>[] measurements)
{
    var sb = new StringBuilder();
    var maxHeight = measurements.Max(measurement => measurement.Item1);

    for (var h = maxHeight; h > 0; h--)
    {
        foreach (var measurement in measurements)
        {
            // If you're on the top or bottom row of a rectangle...
            if (h == 0 || measurement.Item1 == h)
            {
                sb.Append(String.Format("{0}{1}{0}", "+", new String('-', measurement.Item2 - 2)));
                continue;
            }

            // If you're in the middle of a rectangle...
            if (measurement.Item1 > h)
            {
                sb.Append(String.Format("{0}{1}{0}", "+", new String(' ', measurement.Item2 - 2)));
                continue;
            }

            sb.Append(new String(' ', measurement.Item2));
        }

        sb.Append(Environment.NewLine);
    }

    return sb.ToString();
}

Usage:

var output = DrawRectangles(new Tuple(8, 8), new Tuple(4, 3), etc...);

Answer 2

insted of this code

string first = "+" + " -".StringMultiplier(width-1)+ " + ";

you can simply use this pattern:

string first = string.Format("+{0}+", new string('-', width - 2));