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Diffstat (limited to 'Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Folding/XmlFoldingStrategy.cs')
| -rw-r--r-- | Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Folding/XmlFoldingStrategy.cs | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Folding/XmlFoldingStrategy.cs b/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Folding/XmlFoldingStrategy.cs new file mode 100644 index 000000000..0f888a572 --- /dev/null +++ b/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Folding/XmlFoldingStrategy.cs @@ -0,0 +1,215 @@ +// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt) +// This code is distributed under the GNU LGPL (for details please see \doc\license.txt) + +using System; +using System.Collections.Generic; +using System.Linq; +using System.Text; +using System.Xml; + +using Tango.Scripting.Editors.Document; + +namespace Tango.Scripting.Editors.Folding +{ + /// <summary> + /// Holds information about the start of a fold in an xml string. + /// </summary> + sealed class XmlFoldStart : NewFolding + { + internal int StartLine; + } + + /// <summary> + /// Determines folds for an xml string in the editor. + /// </summary> + public class XmlFoldingStrategy : AbstractFoldingStrategy + { + /// <summary> + /// Flag indicating whether attributes should be displayed on folded + /// elements. + /// </summary> + public bool ShowAttributesWhenFolded { get; set; } + + /// <summary> + /// Create <see cref="NewFolding"/>s for the specified document. + /// </summary> + public override IEnumerable<NewFolding> CreateNewFoldings(TextDocument document, out int firstErrorOffset) + { + try { + XmlTextReader reader = new XmlTextReader(document.CreateReader()); + reader.XmlResolver = null; // don't resolve DTDs + return CreateNewFoldings(document, reader, out firstErrorOffset); + } catch (XmlException) { + firstErrorOffset = 0; + return Enumerable.Empty<NewFolding>(); + } + } + + /// <summary> + /// Create <see cref="NewFolding"/>s for the specified document. + /// </summary> + public IEnumerable<NewFolding> CreateNewFoldings(TextDocument document, XmlReader reader, out int firstErrorOffset) + { + Stack<XmlFoldStart> stack = new Stack<XmlFoldStart>(); + List<NewFolding> foldMarkers = new List<NewFolding>(); + try { + while (reader.Read()) { + switch (reader.NodeType) { + case XmlNodeType.Element: + if (!reader.IsEmptyElement) { + XmlFoldStart newFoldStart = CreateElementFoldStart(document, reader); + stack.Push(newFoldStart); + } + break; + + case XmlNodeType.EndElement: + XmlFoldStart foldStart = stack.Pop(); + CreateElementFold(document, foldMarkers, reader, foldStart); + break; + + case XmlNodeType.Comment: + CreateCommentFold(document, foldMarkers, reader); + break; + } + } + firstErrorOffset = -1; + } catch (XmlException ex) { + // ignore errors at invalid positions (prevent ArgumentOutOfRangeException) + if (ex.LineNumber >= 1 && ex.LineNumber <= document.LineCount) + firstErrorOffset = document.GetOffset(ex.LineNumber, ex.LinePosition); + else + firstErrorOffset = 0; + } + foldMarkers.Sort((a,b) => a.StartOffset.CompareTo(b.StartOffset)); + return foldMarkers; + } + + static int GetOffset(TextDocument document, XmlReader reader) + { + IXmlLineInfo info = reader as IXmlLineInfo; + if (info != null && info.HasLineInfo()) { + return document.GetOffset(info.LineNumber, info.LinePosition); + } else { + throw new ArgumentException("XmlReader does not have positioning information."); + } + } + + /// <summary> + /// Creates a comment fold if the comment spans more than one line. + /// </summary> + /// <remarks>The text displayed when the comment is folded is the first + /// line of the comment.</remarks> + static void CreateCommentFold(TextDocument document, List<NewFolding> foldMarkers, XmlReader reader) + { + string comment = reader.Value; + if (comment != null) { + int firstNewLine = comment.IndexOf('\n'); + if (firstNewLine >= 0) { + + // Take off 4 chars to get the actual comment start (takes + // into account the <!-- chars. + + int startOffset = GetOffset(document, reader) - 4; + int endOffset = startOffset + comment.Length + 7; + + string foldText = String.Concat("<!--", comment.Substring(0, firstNewLine).TrimEnd('\r') , "-->"); + foldMarkers.Add(new NewFolding(startOffset, endOffset) { Name = foldText } ); + } + } + } + + /// <summary> + /// Creates an XmlFoldStart for the start tag of an element. + /// </summary> + XmlFoldStart CreateElementFoldStart(TextDocument document, XmlReader reader) + { + // Take off 1 from the offset returned + // from the xml since it points to the start + // of the element name and not the beginning + // tag. + //XmlFoldStart newFoldStart = new XmlFoldStart(reader.Prefix, reader.LocalName, reader.LineNumber - 1, reader.LinePosition - 2); + XmlFoldStart newFoldStart = new XmlFoldStart(); + + IXmlLineInfo lineInfo = (IXmlLineInfo)reader; + newFoldStart.StartLine = lineInfo.LineNumber; + newFoldStart.StartOffset = document.GetOffset(newFoldStart.StartLine, lineInfo.LinePosition - 1); + + if (this.ShowAttributesWhenFolded && reader.HasAttributes) { + newFoldStart.Name = String.Concat("<", reader.Name, " ", GetAttributeFoldText(reader), ">"); + } else { + newFoldStart.Name = String.Concat("<", reader.Name, ">"); + } + + return newFoldStart; + } + + /// <summary> + /// Create an element fold if the start and end tag are on + /// different lines. + /// </summary> + static void CreateElementFold(TextDocument document, List<NewFolding> foldMarkers, XmlReader reader, XmlFoldStart foldStart) + { + IXmlLineInfo lineInfo = (IXmlLineInfo)reader; + int endLine = lineInfo.LineNumber; + if (endLine > foldStart.StartLine) { + int endCol = lineInfo.LinePosition + reader.Name.Length + 1; + foldStart.EndOffset = document.GetOffset(endLine, endCol); + foldMarkers.Add(foldStart); + } + } + + /// <summary> + /// Gets the element's attributes as a string on one line that will + /// be displayed when the element is folded. + /// </summary> + /// <remarks> + /// Currently this puts all attributes from an element on the same + /// line of the start tag. It does not cater for elements where attributes + /// are not on the same line as the start tag. + /// </remarks> + static string GetAttributeFoldText(XmlReader reader) + { + StringBuilder text = new StringBuilder(); + + for (int i = 0; i < reader.AttributeCount; ++i) { + reader.MoveToAttribute(i); + + text.Append(reader.Name); + text.Append("="); + text.Append(reader.QuoteChar.ToString()); + text.Append(XmlEncodeAttributeValue(reader.Value, reader.QuoteChar)); + text.Append(reader.QuoteChar.ToString()); + + // Append a space if this is not the + // last attribute. + if (i < reader.AttributeCount - 1) { + text.Append(" "); + } + } + + return text.ToString(); + } + + /// <summary> + /// Xml encode the attribute string since the string returned from + /// the XmlTextReader is the plain unencoded string and .NET + /// does not provide us with an xml encode method. + /// </summary> + static string XmlEncodeAttributeValue(string attributeValue, char quoteChar) + { + StringBuilder encodedValue = new StringBuilder(attributeValue); + + encodedValue.Replace("&", "&"); + encodedValue.Replace("<", "<"); + encodedValue.Replace(">", ">"); + + if (quoteChar == '"') { + encodedValue.Replace("\"", """); + } else { + encodedValue.Replace("'", "'"); + } + + return encodedValue.ToString(); + } + } +} |