GetSelection Method

In This Topic

Description

Get selection Offset and Length in HTML buffer.

Syntax

Visual Basic
Public Sub GetSelection( _ ByVal Selector As String, _ ByRef Offset As Long, _ ByRef Length As Long _ )

Visual Basic

Public Sub GetSelection( _
   ByVal Selector As String, _
   ByRef Offset As Long, _
   ByRef Length As Long _
)

Parameters

Selector

CSS3 Selector of the element to get selection.

If you are unfamiliar with CSS3 Selectors have a look in Finding the correct CSS3 Selector article.

Offset

The selection Offset.

Length

The selection Length.

Remarks

This method is used for synchronizing editing between HTML5 Visual Editor of WebKitX ActiveX and a Text Editor in FrontPage and Dreamweaver fashion.

Example

Example (Visual Basic)
Example (C#)

Private Sub SelectSource(ByVal Selector As String)
    
    On Error Resume Next
    
    NoDomModifications = True
    
    Dim Offset As Long
    Dim Length As Long
    Dim Sel As New Range
    Dim Pos As Position
    Dim VisibleLinesCount As Long
    Dim TopIndex As Long
    Dim SelLines As Long
    
    CurrentSelector = Selector
    
    WebKitX1.GetSelection Selector, Offset, Length
    
    ' Selection Offset
    Set Pos = Editor.OffsetToPos(Offset)
    Sel.StartLineNo = Pos.LineNo
    Sel.StartColNo = Pos.ColNo
    
    ' Selection Length
    Set Pos = Editor.OffsetToPos(Offset + Length)
    Sel.EndLineNo = Pos.LineNo
    Sel.EndColNo = Pos.ColNo
    
    ' Normalize
    Sel.Normalize
    
    ' Number of selected lines
    SelLines = Sel.EndLineNo - Sel.StartLineNo
    
    ' Number of visible lines
    VisibleLinesCount = Editor.GetVisibleLineCount(0, True)
    
    ' Center selection in editor view
    If SelLines < VisibleLinesCount Then
        
        ' Select!
        Editor.SetSel Sel, False

        TopIndex = Sel.StartLineNo - (VisibleLinesCount - SelLines) / 2
        If TopIndex + VisibleLinesCount > Editor.LineCount Then
            TopIndex = Editor.LineCount - VisibleLinesCount
        End If
        If TopIndex < 0 Then TopIndex = 0
        Editor.TopIndex = TopIndex
    
    End If
        
    Editor.SetSel Sel, True
    
    NoDomModifications = False

End Sub

private void SelectSource(string selector)
{
    NoDomModifications = true;
    int offset = 0, length = 0, VisibleLinesCount, TopIndex, SelLines;
    Range sel = new Range();
    Position pos = new Position();
    CurrentSelector = selector;
    WebKitXCEF31.GetSelection(selector, ref offset, ref length);

    pos = Editor.OffsetToPos(offset);
    sel.StartLineNo = pos.LineNo;
    sel.StartColNo = pos.ColNo;

    pos = Editor.OffsetToPos(offset + length);
    sel.EndLineNo = pos.LineNo;
    sel.EndColNo = pos.ColNo;

    sel.Normalize();
    SelLines = sel.EndLineNo - sel.StartLineNo;
    VisibleLinesCount = Editor.GetVisibleLineCount(0, true);
    if (SelLines < VisibleLinesCount)
    {
        Editor.SetSel(sel, false);
        TopIndex = sel.StartLineNo - (VisibleLinesCount - SelLines) / 2;
        if (TopIndex + VisibleLinesCount > Editor.LineCount)
        {
            TopIndex = Editor.LineCount - VisibleLinesCount;
        }
        if (TopIndex < 0)
        {
            TopIndex = 0;
        }
        Editor.TopIndex = TopIndex;
    }
    Editor.SetSel(sel, true);
    NoDomModifications = false;
}