private void DoBackgroundColorizing(object sender, DoWorkEventArgs e)
{
// Design Notes:
// -------------------------------------------------------------------
//
// It takes a long time, maybe 10s or more, to colorize the XML
// syntax in an xml file 100k in size. Therefore, to maintain UI
// responsiveness, it's necessary to perform the syntax highlighting
// asynchronously.
//
// This method runs endlessly. The first thing it does is wait for a
// signal on the wantFormat event. This event is set when an XML file
// is loaded, or when the text in the richtextbox changes.
//
// When the signal is received, execution continues, and the
// highlighting begins. The approach is this: read a segment of the
// XML, decide how to highlight it, then place a description of that
// formatting change into a list. Then, continue by reading the next
// segment of XML, until the entire XML document has been processed.
//
// On an interval that is normally every 1/48th of the lines - if
// there are 960 lines, then every 20 lines - this method does two
// things: call the progress update for the BG worker, and also apply
// the queued changes. Using this approach the progress bar magically
// appears while highlighting is happening, and disappears when
// highlighting finishes.
//
// The reason for the batch approach: the control.Invoke() method,
// necessary to apply changes to the richtextbox, can be costly. Batching
// changes amortizes the cost of that method across a number of format
// changes.
//
// The ApplyChanges method applies the batch of changes. It first
// does a richtextbox.Invoke() to get on the proper thread. Once
// there, it saves the scroll and selection state, applies each
// formatting change in the list to the rtb text, restores the scroll
// and selection state, and then calls Refresh() on the RTB. After
// that method returns, this method clears the list of format changes
// and continues reading and analyzing the next segment of XML.
//
// If at any time, the user changes the RTB text, either through a new
// load of an XML file, or through direct editing in the richtextbox,
// the main UI signals the wantFormat event again. This method treats
// the raising of that signal as a "cancel-and-restart" message. Upon
// detecting that signal, this method stops working, if it was
// working, and then starts reading and highlighting at the beginning
// again.
//
// There's also some logic to delay the formatting, to wait for the
// user to stop typing, if that is what caused the wantFormat to get
// signalled.
//
// When this method finishes highlighting, this method waits for the
// wantFormat signal again. This method never returns.
//
BackgroundWorker self = sender as BackgroundWorker;
// var xmlReaderSettings = new XmlReaderSettings
// {
// ProhibitDtd = false,
// XmlResolver = new Ionic.Xml.XhtmlResolver()
//
// // this works in .NET 4.0 ??
// //DtdProcessing = DtdProcessing.Parse,
// //XmlResolver =
// //new XmlPreloadedResolver(new XmlXapResolver(),
// //XmlKnownDtds.Xhtml10)
// };
do
{
InvokeActionProperly(SaveCaretPosition);
try
{
InvokeActionProperly(resume);
wantFormat.WaitOne();
wantFormat.Reset();
progressCount = 0;
var list = new List<FormatChange>();
// We want a re-format, but let's wait til
// the user stops typing...
if (_lastRtbKeyPress != _originDateTime)
{
System.Threading.Thread.Sleep(DELAY_IN_MILLISECONDS);
System.DateTime now = System.DateTime.Now;
var _delta = now - _lastRtbKeyPress;
if (_delta < new System.TimeSpan(0, 0, 0, 0, DELAY_IN_MILLISECONDS))
continue;
}
InvokeActionProperly(suspend);
// Get the text ONCE. In a RichTextBox, this is
// expensive, so we do it once, until a change is detected
// in the richtextbox.
string txt = (this.richTextBox1.InvokeRequired)
? (string)this.richTextBox1.Invoke((System.Func<string>)(() => this.richTextBox1.Text))
: this.richTextBox1.Text;
ResetXmlTextBox();
var lc = new LineCalculator(txt);
float maxLines = (float)lc.CountLines();
int reportingInterval = (maxLines > 96)
? (int)(maxLines / 48)
: 4;
int lastReport = -1;
var sr = new StringReader(txt);
XmlReader reader = XmlReader.Create(sr, readerSettings);
IXmlLineInfo rinfo = (IXmlLineInfo)reader;
if (!rinfo.HasLineInfo()) continue;
int rcount = 0;
int ix = 0;
int t = 0;
while (reader.Read())
{
if ((rcount % 8) == 0)
{
// If another format is pending, that means
// the text has changed and we should stop this
// formatting effort and start again.
if (wantFormat.WaitOne(0, false))
break;
}
rcount++;
// report progress
if ((rinfo.LineNumber / reportingInterval) > lastReport)
{
int pct = (int)((float)rinfo.LineNumber / maxLines * 100);
self.ReportProgress(pct);
lastReport = (rinfo.LineNumber / reportingInterval);
ApplyChanges(list);
list.Clear();
progressCount++;
}
switch (reader.NodeType)
{
case XmlNodeType.XmlDeclaration: // The node is an declaration.
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) +
rinfo.LinePosition - 1;
t = 2 + reader.Name.Length + 1 + reader.Value.Length + 2;
list.Add(new FormatChange(ix - 2, t, Color.Blue));
break;
case XmlNodeType.DocumentType: // DTD
break;
case XmlNodeType.ProcessingInstruction:
// eg, <?xml-stylesheet type="text/xsl" href="http://www.codeplex.com/rss.xsl"?>
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) + rinfo.LinePosition - 1;
t = 2 + reader.Name.Length + 1 + reader.Value.Length + 2;
list.Add(new FormatChange(ix - 2, t, Color.Blue));
break;
case XmlNodeType.Element: // The node is an element.
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) +
rinfo.LinePosition - 1;
list.Add(new FormatChange(ix - 1, 1, Color.Blue));
list.Add(new FormatChange(ix, reader.Name.Length, Color.DarkRed));
if (reader.HasAttributes)
{
reader.MoveToFirstAttribute();
do
{
//string s = reader.Value;
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) +
+ rinfo.LinePosition - 1;
list.Add(new FormatChange(ix, reader.Name.Length, Color.Red));
ix += reader.Name.Length;
ix = txt.IndexOf('=', ix);
// make the equals sign blue
list.Add(new FormatChange(ix, 1, Color.Blue));
// skip over the quote char (it remains black)
ix = txt.IndexOf(reader.QuoteChar, ix);
ix++;
// highlight the value of the attribute as blue
if (txt.Substring(ix).StartsWith(reader.Value))
{
list.Add(new FormatChange(ix, reader.Value.Length, Color.Blue));
}
else
{
// Difference in escaping. The InnerXml may include
// \" where " is in the doc.
string s = reader.Value.XmlEscapeQuotes();
int delta = s.Length - reader.Value.Length;
list.Add(new FormatChange(ix, reader.Value.Length + delta, Color.Blue));
}
}
while (reader.MoveToNextAttribute());
ix = txt.IndexOf('>', ix);
// the close-angle-bracket
if (txt[ix - 1] == '/')
{
list.Add(new FormatChange(ix - 1, 2, Color.Blue));
}
else
{
list.Add(new FormatChange(ix, 1, Color.Blue));
}
}
break;
case XmlNodeType.Text:
// Leave these black - no addl formatting
break;
case XmlNodeType.EndElement:
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) +
+rinfo.LinePosition - 1;
list.Add(new FormatChange(ix - 2, 2, Color.Blue));
list.Add(new FormatChange(ix, reader.Name.Length, Color.DarkRed));
list.Add(new FormatChange(ix + reader.Name.Length, 1, Color.Blue));
break;
case XmlNodeType.Attribute:
// These are handed within XmlNodeType.Element
break;
case XmlNodeType.Comment:
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) +
+rinfo.LinePosition - 1;
list.Add(new FormatChange(ix, reader.Value.Length, Color.Green));
break;
}
}
// in case there are more
ApplyChanges(list);
self.ReportProgress(100);
}
catch (Exception exc1)
{
// this can happen when editing an XML file, and the
// xurrent state of the document is not valid xml.
NotifyStopFormatting(exc1.Message);
// System.Windows.Forms.MessageBox.Show("Exception: " + exc1.Message,
// "Exception while formatting",
// System.Windows.Forms.MessageBoxButtons.OK,
// System.Windows.Forms.MessageBoxIcon.Error);
}
finally
{
//RestoreCaretPosition();
}
}
while (true);
}
private void DoBackgroundColorizing(object sender, DoWorkEventArgs e)
{
// Design Notes:
// -------------------------------------------------------------------
//
// It takes a long time, maybe 10s or more, to colorize the XML
// syntax in an xml file 100k in size. Therefore, to maintain UI
// responsiveness, it's necessary to perform the syntax highlighting
// asynchronously.
//
// This method runs endlessly. The first thing it does is wait for a
// signal on the wantFormat event. This event is set when an XML file
// is loaded, or when the text in the richtextbox changes.
//
// When the signal is received, execution continues, and the
// highlighting begins. The approach is this: read a segment of the
// XML, decide how to highlight it, then place a description of that
// formatting change into a list. Then, continue by reading the next
// segment of XML, until the entire XML document has been processed.
//
// On an interval that is normally every 1/48th of the lines - if
// there are 960 lines, then every 20 lines - this method does two
// things: call the progress update for the BG worker, and also apply
// the queued changes. Using this approach the progress bar magically
// appears while highlighting is happening, and disappears when
// highlighting finishes.
//
// The reason for the batch approach: the control.Invoke() method,
// necessary to apply changes to the richtextbox, can be costly. Batching
// changes amortizes the cost of that method across a number of format
// changes.
//
// The ApplyChanges method applies the batch of changes. It first
// does a richtextbox.Invoke() to get on the proper thread. Once
// there, it saves the scroll and selection state, applies each
// formatting change in the list to the rtb text, restores the scroll
// and selection state, and then calls Refresh() on the RTB. After
// that method returns, this method clears the list of format changes
// and continues reading and analyzing the next segment of XML.
//
// If at any time, the user changes the RTB text, either through a new
// load of an XML file, or through direct editing in the richtextbox,
// the main UI signals the wantFormat event again. This method treats
// the raising of that signal as a "cancel-and-restart" message. Upon
// detecting that signal, this method stops working, if it was
// working, and then starts reading and highlighting at the beginning
// again.
//
// There's also some logic to delay the formatting, to wait for the
// user to stop typing, if that is what caused the wantFormat to get
// signalled.
//
// When this method finishes highlighting, this method waits for the
// wantFormat signal again. This method never returns.
//
BackgroundWorker self = sender as BackgroundWorker;
// var xmlReaderSettings = new XmlReaderSettings
// {
// ProhibitDtd = false,
// XmlResolver = new Ionic.Xml.XhtmlResolver()
//
// // this works in .NET 4.0 ??
// //DtdProcessing = DtdProcessing.Parse,
// //XmlResolver =
// //new XmlPreloadedResolver(new XmlXapResolver(),
// //XmlKnownDtds.Xhtml10)
// };
do
{
InvokeActionProperly(SaveCaretPosition);
try
{
InvokeActionProperly(resume);
wantFormat.WaitOne();
wantFormat.Reset();
progressCount = 0;
var list = new List <FormatChange>();
// We want a re-format, but let's wait til
// the user stops typing...
if (_lastRtbKeyPress != _originDateTime)
{
System.Threading.Thread.Sleep(DELAY_IN_MILLISECONDS);
System.DateTime now = System.DateTime.Now;
var _delta = now - _lastRtbKeyPress;
if (_delta < new System.TimeSpan(0, 0, 0, 0, DELAY_IN_MILLISECONDS))
{
continue;
}
}
InvokeActionProperly(suspend);
// Get the text ONCE. In a RichTextBox, this is
// expensive, so we do it once, until a change is detected
// in the richtextbox.
string txt = (this.richTextBox1.InvokeRequired)
? (string)this.richTextBox1.Invoke((System.Func <string>)(() => this.richTextBox1.Text))
: this.richTextBox1.Text;
ResetXmlTextBox();
var lc = new LineCalculator(txt);
float maxLines = (float)lc.CountLines();
int reportingInterval = (maxLines > 96)
? (int)(maxLines / 48)
: 4;
int lastReport = -1;
var sr = new StringReader(txt);
XmlReader reader = XmlReader.Create(sr, readerSettings);
IXmlLineInfo rinfo = (IXmlLineInfo)reader;
if (!rinfo.HasLineInfo())
{
continue;
}
int rcount = 0;
int ix = 0;
int t = 0;
while (reader.Read())
{
if ((rcount % 8) == 0)
{
// If another format is pending, that means
// the text has changed and we should stop this
// formatting effort and start again.
if (wantFormat.WaitOne(0, false))
{
break;
}
}
rcount++;
// report progress
if ((rinfo.LineNumber / reportingInterval) > lastReport)
{
int pct = (int)((float)rinfo.LineNumber / maxLines * 100);
self.ReportProgress(pct);
lastReport = (rinfo.LineNumber / reportingInterval);
ApplyChanges(list);
list.Clear();
progressCount++;
}
switch (reader.NodeType)
{
case XmlNodeType.XmlDeclaration: // The node is an declaration.
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) +
rinfo.LinePosition - 1;
t = 2 + reader.Name.Length + 1 + reader.Value.Length + 2;
list.Add(new FormatChange(ix - 2, t, Color.Blue));
break;
case XmlNodeType.DocumentType: // DTD
break;
case XmlNodeType.ProcessingInstruction:
// eg, <?xml-stylesheet type="text/xsl" href="http://www.codeplex.com/rss.xsl"?>
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) + rinfo.LinePosition - 1;
t = 2 + reader.Name.Length + 1 + reader.Value.Length + 2;
list.Add(new FormatChange(ix - 2, t, Color.Blue));
break;
case XmlNodeType.Element: // The node is an element.
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) +
rinfo.LinePosition - 1;
list.Add(new FormatChange(ix - 1, 1, Color.Blue));
list.Add(new FormatChange(ix, reader.Name.Length, Color.DarkRed));
if (reader.HasAttributes)
{
reader.MoveToFirstAttribute();
do
{
//string s = reader.Value;
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) +
+rinfo.LinePosition - 1;
list.Add(new FormatChange(ix, reader.Name.Length, Color.Red));
ix += reader.Name.Length;
ix = txt.IndexOf('=', ix);
// make the equals sign blue
list.Add(new FormatChange(ix, 1, Color.Blue));
// skip over the quote char (it remains black)
ix = txt.IndexOf(reader.QuoteChar, ix);
ix++;
// highlight the value of the attribute as blue
if (txt.Substring(ix).StartsWith(reader.Value))
{
list.Add(new FormatChange(ix, reader.Value.Length, Color.Blue));
}
else
{
// Difference in escaping. The InnerXml may include
// \" where " is in the doc.
string s = reader.Value.XmlEscapeQuotes();
int delta = s.Length - reader.Value.Length;
list.Add(new FormatChange(ix, reader.Value.Length + delta, Color.Blue));
}
}while (reader.MoveToNextAttribute());
ix = txt.IndexOf('>', ix);
// the close-angle-bracket
if (txt[ix - 1] == '/')
{
list.Add(new FormatChange(ix - 1, 2, Color.Blue));
}
else
{
list.Add(new FormatChange(ix, 1, Color.Blue));
}
}
break;
case XmlNodeType.Text:
// Leave these black - no addl formatting
break;
case XmlNodeType.EndElement:
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) +
+rinfo.LinePosition - 1;
list.Add(new FormatChange(ix - 2, 2, Color.Blue));
list.Add(new FormatChange(ix, reader.Name.Length, Color.DarkRed));
list.Add(new FormatChange(ix + reader.Name.Length, 1, Color.Blue));
break;
case XmlNodeType.Attribute:
// These are handed within XmlNodeType.Element
break;
case XmlNodeType.Comment:
ix = lc.GetCharIndexFromLine(rinfo.LineNumber - 1) +
+rinfo.LinePosition - 1;
list.Add(new FormatChange(ix, reader.Value.Length, Color.Green));
break;
}
}
// in case there are more
ApplyChanges(list);
self.ReportProgress(100);
}
catch (Exception exc1)
{
// this can happen when editing an XML file, and the
// xurrent state of the document is not valid xml.
NotifyStopFormatting(exc1.Message);
// System.Windows.Forms.MessageBox.Show("Exception: " + exc1.Message,
// "Exception while formatting",
// System.Windows.Forms.MessageBoxButtons.OK,
// System.Windows.Forms.MessageBoxIcon.Error);
}
finally
{
//RestoreCaretPosition();
}
}while (true);
}
