I have just tried setting both EnableStyledText and PolygonalTextLayout to true for the boxes in my chart.

While editing chart boxes, I resize the temporary edit control and the box in question to fit the newly entered text. With the above two variables set to true, the temporary edit control and chart box both move down the screen as I enter characters. This does not happen with these variables set to false.

On investigation, the ResizeToFitText function changes the Y position of box it is called on. This did not happen before. My code looks like this...

protected void TextBox_TextChanged(object sender, EventArgs e)
{
Debug.Print("Edited box bounds = " + EditedBox.Bounds.X + " " + EditedBox.Bounds.Y);

using var tempBox = new ShapeNode(EditedBox);
tempBox.Text = TempEditControl.Text;

// If text ends with a 'New Line', add something onto the end of the text otherwise
// the top line is lost

if (tempBox.Text.EndsWith(Environment.NewLine, StringComparison.OrdinalIgnoreCase))
tempBox.Text += "Abc123";

tempBox.ResizeToFitText(FitSize.KeepWidth);
Debug.Print("After ResizeToFitText - tempBox bounds = " + tempBox.Bounds.X + " " + tempBox.Bounds.Y);

EditedBox.Bounds = tempBox.Bounds;

var clientRect = FlowChartView.DocToClient(tempBox.Bounds);

TempEditControl.Location = clientRect.Location;
TempEditControl.Size = clientRect.Size;

Debug.Print("--------------------------------------");
}

Is this a bug? Is there a work-around I can use.

Regards
DavidL

Sorry I missed your reply before adding some text to the original post. I said...

I have got around the problem by saving and restoring the original Y position of the box being edited, so no big issue.

However, new issue...

Is it possible to have a version of ResizeToFitText that takes into account the bold, italic and underline tags such as <b> </b>. With the current version and bold, italic and underlined text, the above code will produce an edit box that does not fit all the characters.

DavidL

Thanks, that is very helpful.  This is the final version if it helps anyone. The TextFormatFlags.TextBoxControl seemed to be very necessary and I have set a minimum height...

private void ResizeMultilineTextBox(DragTextBox textBox)
{
    string textToMeasure = textBox.Text;

    if (textBox.Text.EndsWith(Environment.NewLine, StringComparison.OrdinalIgnoreCase))
        textToMeasure += "Abc123";

    var size = TextRenderer.MeasureText(textToMeasure,
                                        textBox.Font,
                                        new Size(textBox.Width, int.MaxValue),
                                        TextFormatFlags.WordBreak | TextFormatFlags.TextBoxControl);

    var minBoxHeight = FlowChartView.DocToClient(EditedBox.Bounds).Height;

    if (size.Height < minBoxHeight)
        textBox.Height = minBoxHeight;
    else
        textBox.Height = size.Height;
}