Word wrap a a string in multiple lines

Question

I am trying to word wrap a string into multiple lines whit every line respecting a defined width.

For example word wrap the following text to fit an area of 120 pixels in width.

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I am using C#.

Answer 1

The following code, taken from this blogpost, will help to get your job done.

You can use it this way:

string wordWrappedText = WordWrap( <yourtext>, 120 );

Please note that the code is not mine, I am just reporting here the main function for your commodity.

public static string WordWrap( string the_string, int width ) {
    int pos, next;
    StringBuilder sb = new StringBuilder();

    // Lucidity check
    if ( width < 1 )
        return the_string;

    // Parse each line of text
    for ( pos = 0; pos < the_string.Length; pos = next ) {
        // Find end of line
        int eol = the_string.IndexOf( _newline, pos );

        if ( eol == -1 )
            next = eol = the_string.Length;
        else
            next = eol + _newline.Length;

        // Copy this line of text, breaking into smaller lines as needed
        if ( eol > pos ) {
            do {
                int len = eol - pos;

                if ( len > width )
                    len = BreakLine( the_string, pos, width );

                sb.Append( the_string, pos, len );
                sb.Append( _newline );

                // Trim whitespace following break
                pos += len;

                while ( pos < eol && Char.IsWhiteSpace( the_string[pos] ) )
                    pos++;

            } while ( eol > pos );
        } else sb.Append( _newline ); // Empty line
    }

    return sb.ToString();
}

Answer 2

What type of control contains the text? There are a number of controls you could extend to take advantage of the built-in text wrapping

Answer 3

static void Main(string[] args)
    {
        List<string> lines = WrapText("Add some text", 300, "Calibri", 11);

        foreach (var item in lines)
        {
            Console.WriteLine(item);
        }


        Console.ReadLine();
    }

    static List<string> WrapText(string text, double pixels, string fontFamily, float emSize)
    {
        string[] originalLines = text.Split(new string[] { " " }, StringSplitOptions.None);
        List<string> wrappedLines = new List<string>();

        StringBuilder actualLine = new StringBuilder();
        double actualWidth = 0;

        foreach (var item in originalLines)
        {
            FormattedText formatted = new FormattedText(item, CultureInfo.CurrentCulture, System.Windows.FlowDirection.LeftToRight,
                                      new Typeface(fontFamily), emSize, Brushes.Black);
            actualLine.Append(item + " ");
            actualWidth += formatted.Width;

            if (actualWidth > pixels)
            {
                wrappedLines.Add(actualLine.ToString());
                actualLine.Clear();
                actualWidth = 0;
            }
        }

        return wrappedLines;
    }

Add WindowsBase and PresentationCore libraries.

Answer 4

You can get the (approximate) width of a string from the System.Drawing.Graphics class using the MeasureString() method. If you need a very precise width, I think you have to use the MeasureCharacterRanges() method. Here is some sample code using the MeasureString() method to do roughly what you asked for:

using System;
using System.Collections.Generic; // for List<>
using System.Drawing; // for Graphics and Font

private List<string> GetWordwrapped(string original)
{
    List<string> wordwrapped = new List<string>();

    Graphics graphics = Graphics.FromHwnd(this.Handle);
    Font font = new Font("Arial", 10);

    string currentLine = string.Empty;

    for (int i = 0; i < original.Length; i++)
    {
        char currentChar = original[i];
        currentLine += currentChar;
        if (graphics.MeasureString(currentLine, font).Width > 120)
        {
            // exceeded length, back up to last space
            int moveback = 0;
            while (currentChar != ' ')
            {
                moveback++;
                i--;
                currentChar = original[i];
            }
            string lineToAdd = currentLine.Substring(0, currentLine.Length - moveback);
            wordwrapped.Add(lineToAdd);
            currentLine = string.Empty;
        }
    }

    return wordwrapped;
}