示例#1
0
文件: linebase.cs 项目: JianwenSun/cc
        //-------------------------------------------------------------------
        //
        //  Protected Methods
        //
        //-------------------------------------------------------------------

        #region Protected Methods

        /// <summary>
        /// Fetch the next run at text position. 
        /// </summary>
        /// <param name="position">
        /// Current position in text array
        /// </param>
        /// <returns></returns>
        protected TextRun HandleText(StaticTextPointer position)
        {
            DependencyObject element;
            StaticTextPointer endOfRunPosition;

            Invariant.Assert(position.GetPointerContext(LogicalDirection.Forward) == TextPointerContext.Text, "TextPointer does not point to characters.");

            if (position.Parent != null)
            {
                element = position.Parent;
            }
            else
            {
                element = _paraClient.Paragraph.Element;
            }

            // Extract the aggregated properties into something that the textrun can use.
            // 


            TextProperties textProps = new TextProperties(element, position, false /* inline objects */, true /* get background */);

            // Calculate the end of the run by finding either:
            //      a) the next intersection of highlight ranges, or
            //      b) the natural end of this textrun
            endOfRunPosition = position.TextContainer.Highlights.GetNextPropertyChangePosition(position, LogicalDirection.Forward);

            // Clamp the text run at an arbitrary limit, so we don't make
            // an unbounded allocation.
            if (position.GetOffsetToPosition(endOfRunPosition) > 4096)
            {
                endOfRunPosition = position.CreatePointer(4096);
            }

            // Get character buffer for the text run.
            char[] textBuffer = new char[position.GetOffsetToPosition(endOfRunPosition)];

            // Copy characters from text run into buffer. Note the actual number of characters copied,
            // which may be different than the buffer's length. Buffer length only specifies the maximum
            // number of characters
            int charactersCopied = position.GetTextInRun(LogicalDirection.Forward, textBuffer, 0, textBuffer.Length);

            // Create text run using the actual number of characters copied
            return new TextCharacters(textBuffer, 0, charactersCopied, textProps);
        }
示例#2
0
        //-------------------------------------------------------------------
        //
        //  Private Methods
        //
        //-------------------------------------------------------------------

        #region Private Methods

        /// <summary>
        /// Fetch the next run at text position.
        /// </summary>
        private TextRun HandleText(StaticTextPointer position)
        {
            // Calculate the end of the run by finding either:
            //      a) the next intersection of highlight ranges, or
            //      b) the natural end of this textrun
            StaticTextPointer endOfRunPosition = _owner.Host.TextContainer.Highlights.GetNextPropertyChangePosition(position, LogicalDirection.Forward);

            // Clamp the text run at an arbitrary limit, so we don't make
            // an unbounded allocation.
            if (position.GetOffsetToPosition(endOfRunPosition) > 4096)
            {
                endOfRunPosition = position.CreatePointer(4096);
            }

            // Factor in any speller error squiggles on the run.
            TextDecorationCollection highlightDecorations = position.TextContainer.Highlights.GetHighlightValue(position, LogicalDirection.Forward, typeof(SpellerHighlightLayer)) as TextDecorationCollection;
            TextRunProperties properties;

            if (highlightDecorations == null)
            {
                properties = _lineProperties.DefaultTextRunProperties;
            }
            else
            {
                if (_spellerErrorProperties == null)
                {
                    _spellerErrorProperties = new TextProperties((TextProperties)_lineProperties.DefaultTextRunProperties, highlightDecorations);
                }
                properties = _spellerErrorProperties;
            }

            // Get character buffer for the text run.
            char[] textBuffer = new char[position.GetOffsetToPosition(endOfRunPosition)];

            // Copy characters from text run into buffer. Since we are dealing with plain text content, 
            // we expect to get all the characters from position to endOfRunPosition.
            int charactersCopied = position.GetTextInRun(LogicalDirection.Forward, textBuffer, 0, textBuffer.Length);
            Invariant.Assert(charactersCopied == textBuffer.Length);

            // Create text run, using characters copied as length
            return new TextCharacters(textBuffer, 0, charactersCopied, properties);
        }