Text Justification

Question

I am looking for a c# function or routine that will center justify text.

For example, if I have a sentence, I have noticed that when the sentence is justified to the edges of the screen, that spaces are placed in the line. The inserted spaces start in the center and move out from there on both sides as needed as needed.

Is there a C# function that I can pass my string, say 50 chars, and get back a pretty 56 char string?

Thanks in advance,

Rob

Answer 1

Nice task. Here's a solution based on Linq extension methods. If you do not wish to use them, see history for previous version of code. In this example spaces on the left and right sides from center are 'equal' with respect to order of inserting.

using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    public static String Justify(String s, Int32 count)
    {
        if (count <= 0)
            return s;

        Int32 middle = s.Length / 2;
        IDictionary<Int32, Int32> spaceOffsetsToParts = new Dictionary<Int32, Int32>();
        String[] parts = s.Split(' ');
        for (Int32 partIndex = 0, offset = 0; partIndex < parts.Length; partIndex++)
        {
            spaceOffsetsToParts.Add(offset, partIndex);
            offset += parts[partIndex].Length + 1; // +1 to count space that was removed by Split
        }
        foreach (var pair in spaceOffsetsToParts.OrderBy(entry => Math.Abs(middle - entry.Key)))
        {
            count--;
            if (count < 0)
                break;
            parts[pair.Value] += ' ';
        }
        return String.Join(" ", parts);
    }
    static void Main(String[] args) {
        String s = "skvb sdkvkd s  kc wdkck sdkd sdkje sksdjs skd";
        String j = Justify(s, 5);
        Console.WriteLine("Initial: " + s);
        Console.WriteLine("Result:  " + j);
        Console.ReadKey();
    }
}