//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(" ".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); } } }