//Microsoft Public License (Ms-PL)
//http://visualizer.codeplex.com/license
using System;
using System.Collections.Generic;
namespace Redwerb.BizArk.Core.StringExt
{
/// <summary>
/// Provides extension methods for strings.
/// </summary>
public static class StringExt
{
/// <summary>
/// Forces the string to word wrap so that each line doesn't exceed the maxLineLength.
/// </summary>
/// <param name="str">The string to wrap.</param>
/// <param name="maxLength">The maximum number of characters per line.</param>
/// <returns></returns>
public static string Wrap(this string str, int maxLength)
{
return Wrap(str, maxLength, "");
}
/// <summary>
/// Forces the string to word wrap so that each line doesn't exceed the maxLineLength.
/// </summary>
/// <param name="str">The string to wrap.</param>
/// <param name="maxLength">The maximum number of characters per line.</param>
/// <param name="prefix">Adds this string to the beginning of each line.</param>
/// <returns></returns>
public static string Wrap(this string str, int maxLength, string prefix)
{
if (string.IsNullOrEmpty(str)) return "";
if (maxLength <= 0) return prefix + str;
var lines = new List<string>();
// breaking the string into lines makes it easier to process.
foreach (string line in str.Split("\n".ToCharArray()))
{
var remainingLine = line.Trim();
do
{
var newLine = GetLine(remainingLine, maxLength - prefix.Length);
lines.Add(newLine);
remainingLine = remainingLine.Substring(newLine.Length).Trim();
// Keep iterating as int as we've got words remaining
// in the line.
} while (remainingLine.Length > 0);
}
return string.Join(Environment.NewLine + prefix, lines.ToArray());
}
private static string GetLine(string str, int maxLength)
{
// The string is less than the max length so just return it.
if (str.Length <= maxLength) return str;
// Search backwords in the string for a whitespace char
// starting with the char one after the maximum length
// (if the next char is a whitespace, the last word fits).
for (int i = maxLength; i >= 0; i--)
{
if (char.IsWhiteSpace(str[i]))
return str.Substring(0, i).TrimEnd();
}
// No whitespace chars, just break the word at the maxlength.
return str.Substring(0, maxLength);
}
}
}
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