WPF文本框TextBox获取输入位置坐标

方法一、

 public Point GetPositionFromCharacterIndex(TextBox txtContent)
        {
            int lastIndex = txtContent.GetLastVisibleLineIndex();
            int firstIndex = txtContent.GetFirstVisibleLineIndex();
            int rowCount = lastIndex - firstIndex;
            string lineVal = txtContent.GetLineText(lastIndex);
            Typeface typeface = new Typeface(txtContent.FontFamily,
             txtContent.FontStyle,
             txtContent.FontWeight,
             txtContent.FontStretch);
            FormattedText formattedText = new FormattedText(lineVal,
                CultureInfo.CurrentCulture,
                FlowDirection.LeftToRight,
                typeface, txtContent.FontSize, txtContent.Background);
            double X = 0d;
            double Y = 0d;
            if (lastIndex > 0)
            {
                X = formattedText.Width;
                Y = rowCount * formattedText.Height > txtContent.ActualHeight ? (txtContent.ActualHeight - pp.Height - formattedText.Height) : ((rowCount - 1) * formattedText.Height - pp.Height);
            }
            else
            {
                X = formattedText.Width;
                Y = -pp.Height;
            }
            Point point = new Point(X, Y);
            return point;
        }

　　方法二、

        [DllImport("user32")]
        public static extern bool GetCaretPos(out System.Drawing.Point lpPoint);