Code Summary | Javaв„ў EE 5 Tutorial, The (3rd Edition)

The class, with things rearranged a bit, looks like this now:

 using System; 
 using System.Collections; 
 using System.Text; 
 using System.Text.RegularExpressions; 
 namespace Notepad { 
 class TextModel { 
 private static string[] newParagraph = { "<P></P>" }; 
 private static string paragraphSkip = "<P>"; 
 private static string[] newSection = 
 {"<sect1><title></title>","</sect1>" }; 
 private static string sectionSkip = "<sect1><title>"; 
 private ArrayList lines; 
 private int selectionStart; 
 public TextModel() {       lines = new ArrayList(); 
 } 
 public ArrayList Lines { 
 get { 
 return lines; 
 } 
 set { 
 lines = value; 
 } 
 } 
 public void SetLines(String[] lines) { 
 this.Lines = new ArrayList(lines); 
 } 
 public String[] LinesArray() { 
 String[] result = new String[lines.Count]; 
 lines.CopyTo(result); 
 return result; 
 } 
 public String TestText { 
 get { 
 StringBuilder b = new StringBuilder(); 
 foreach(String s in lines) { 
 b.Append(s); 
 b.Append(System.Environment.NewLine); 
 } 
 b.Insert(SelectionStart,""); 
 return b.ToString(); 
 } 
 } 
 public int SelectionStart { 
 get { 
 return selectionStart; 
 } 
 set { 
 selectionStart = value; 
 } 
 } 
 public void Enter() { 
 InsertParagraphTag(); 
 } 
 public void InsertParagraphTag() { 
 InsertTags(newParagraph, paragraphSkip); 
 } 
 public void AltS() { 
 InsertSectionTags(); 
 } 
 public void InsertSectionTags() { 
 InsertTags(newSection, sectionSkip); 
 } 
 private void InsertTags(string[] tagsToInsert, string tagsPrecedingCursor)        { 
 int cursorLine = LineContainingCursor(); 
 lines.InsertRange(cursorLine+1, tagsToInsert); 
 selectionStart = NewSelectionStart(cursorLine + 1, tagsPrecedingCursor); 
 } 
 private int NewSelectionStart(int cursorLine, string tags) { 
 return SumLineLengths(cursorLine) + tags.Length; 
 } 
 private int SumLineLengths(int cursorLine) { 
 int length = 0; 
 for (int i = 0; i < cursorLine; i++) 
 length += ((String)lines[i]).Length + Environment.NewLine.Length; 
 return length; 
 } 
 public void ChangeToH2() { 
 ArrayList linesList = Lines; 
 String oldLine = (String) linesList[LineContainingCursor()]; 
 Regex r = new Regex("<(?<prefix>.*)>(?<body>.*)</(?<suffix>.*)>"); 
 Match m = r.Match(oldLine); 
 String newLine = "<H2>" + m.Groups["body"] + "</H2>"; 
 linesList[LineContainingCursor()] = newLine; 
 Lines = linesList; 
 } 
 private int LineContainingCursor() { 
 if (lines.Count == 0) 
 return -1; 
 int length = 0; 
 int lineNr = 0; 
 int cr = Environment.NewLine.Length; 
 foreach ( String s in lines) { 
 if (length <= selectionStart 
 && selectionStart < length+s.Length + cr ) 
 break; 
 length += s.Length + cr; 
 lineNr++; 
 } 
 return lineNr; 
 } 
 } 
 }

By the way, you may have noticed that ChangeToH2 and LineContainingCursor. They re part of an experiment that I haven t written up, in how to change a <P> tag to an <H2>. If I were entirely brave, I d delete the code and the test that uses it until I need it. But I m only human...