PageColumns.cs

using FastReport.Utils;
using System;
using System.ComponentModel;

namespace FastReport
{
    /// <summary>
    /// This class contains the page columns settings. 
    /// It is used in the <see cref="ReportPage.Columns"/> property.
    /// </summary>
    [TypeConverter(typeof(FastReport.TypeConverters.FRExpandableObjectConverter))]
    public class PageColumns
    {
        private int count;
        private float width;
        private FloatCollection positions;
        private ReportPage page;

        /// <summary>
        /// Gets or sets the number of columns.
        /// </summary>
        /// <remarks>
        /// Set this property to 0 or 1 if you don't want to use columns.
        /// </remarks>
        [DefaultValue(1)]
        public int Count
        {
            get { return count; }
            set
            {
                if (value <= 0)
                    throw new ArgumentOutOfRangeException("Count", "Value must be greather than 0");

                count = value;
                width = (page.PaperWidth - page.LeftMargin - page.RightMargin) / count;
                positions.Clear();
                for (int i = 0; i < count; i++)
                {
                    positions.Add(i * Width);
                }
            }
        }

        /// <summary>
        /// Gets or sets the column width.
        /// </summary>
        [TypeConverter("FastReport.TypeConverters.PaperConverter, FastReport")]
        public float Width
        {
            get { return width; }
            set { width = value; }
        }

        /// <summary>
        /// Gets or sets a list of column starting positions.
        /// </summary>
        /// <remarks>
        /// Each value represents a column starting position measured in the millimeters.
        /// </remarks>
        public FloatCollection Positions
        {
            get { return positions; }
            set
            {
                if (value.Count == count)
                {
                    positions = value;
                }
                else
                {
                    positions.Clear();
                    for (int i = 0; i < count; i++)
                    {
                        positions.Add(i * Width);
                    }
                }
            }
        }

        private bool ShouldSerializeWidth()
        {
            return Count > 1;
        }

        private bool ShouldSerializePositions()
        {
            return Count > 1;
        }

        /// <summary>
        /// Assigns values from another source.
        /// </summary>
        /// <param name="source">Source to assign from.</param>
        public void Assign(PageColumns source)
        {
            Count = source.Count;
            Width = source.Width;
            Positions.Assign(source.Positions);
        }

        internal void Serialize(FRWriter writer, PageColumns c)
        {
            if (Count != c.Count)
                writer.WriteInt("Columns.Count", Count);
            if (Count > 1)
            {
                writer.WriteFloat("Columns.Width", Width);
                Positions = Positions; // avoid bug when number of positions is not equal number of columns
                writer.WriteValue("Columns.Positions", Positions);
            }
        }

        internal PageColumns(ReportPage page)
        {
            this.page = page;
            positions = new FloatCollection();
            Count = 1;
        }
    }
}