mono/mcs/class/System.Drawing/System.Drawing.Printing/MarginsConverter.cs

//
// System.Drawing.MarginsConverter.cs
//
// Author:
//   Dennis Hayes ([email protected])
//   Herve Poussineau ([email protected])
//
// (C) 2002 Ximian, Inc
//
using System;
using System.ComponentModel;
using System.Globalization;
using System.Text.RegularExpressions;

namespace System.Drawing.Printing {
	/// <summary>
	/// Summary description for MarginsConverter.
	/// </summary>
	public class MarginsConverter : ExpandableObjectConverter {
		public MarginsConverter() {
		}
		#region Methods
		public override bool CanConvertFrom(ITypeDescriptorContext context,Type sourceType) {
			if (sourceType == typeof(string))
				return true;
			
			return base.CanConvertFrom(context, sourceType);
		}
		
		public override bool CanConvertTo(ITypeDescriptorContext context,Type destinationType) {
			if (destinationType == typeof(string))
				return true;
			
			return base.CanConvertTo(context, destinationType);
		}
		
		public override object ConvertFrom(ITypeDescriptorContext context,CultureInfo culture,object value) {
			if (value is string)
			{
				if (value == null)
					return new Margins();
				
				// format [left];[right];[top];[bottom]
				string separator = @"( |\t)*";
				separator = separator + ";" + separator;
				string regex = @"(?<left>\d+)" + separator + @"(?<right>\d+)" + separator + @"(?<top>\d+)" + separator + @"(?<bottom>\d+)";
				
				Match match = new Regex(regex).Match(value as string);
				if (!match.Success)
					throw new ArgumentException("value");
				
				int left, right, top, bottom;
				try
				{
					left = int.Parse(match.Groups["left"].Value);
					right = int.Parse(match.Groups["right"].Value);
					top = int.Parse(match.Groups["top"].Value);
					bottom = int.Parse(match.Groups["bottom"].Value);
				}
				catch (Exception e)
				{
					throw new ArgumentException("value", e);
				}
				return new Margins(left, right, top, bottom);
			} else
				return base.ConvertFrom(context, culture, value);
		}
		
		public override object ConvertTo(ITypeDescriptorContext context,CultureInfo culture,object value,Type destinationType) {
			if (destinationType == typeof(string) && value is Margins)
			{
				Margins source = value as Margins;
				string ret = "{0}; {1}; {2}; {3}";
				return String.Format(ret, source.Left, source.Right, source.Top, source.Bottom);
			} else
				return base.ConvertTo(context, culture, value, destinationType);
		}
		
		public override bool GetCreateInstanceSupported(ITypeDescriptorContext context)
		{
			return true;
		}
		
		public override object CreateInstance(ITypeDescriptorContext context, System.Collections.IDictionary propertyValues)
		{
			try
			{
				Margins margins = new Margins();
				margins.Left = int.Parse(propertyValues["Left"].ToString());
				margins.Right = int.Parse(propertyValues["Right"].ToString());
				margins.Top = int.Parse(propertyValues["Top"].ToString());
				margins.Bottom = int.Parse(propertyValues["Bottom"].ToString());
				return margins;
			}
			catch (Exception)
			{
				// in case of error, return null
				return null;
			}
		}
		#endregion
	}
}