Traceract

/*
 * Copyright (c) 2004, 2005 MyXaml
 * All Rights Reserved
 * 
 * Licensed under the terms of the GNU General Public License
 * http://www.gnu.org/licenses/licenses.html#GPL
*/

using System;
using System.Collections;
using System.ComponentModel;
using System.Diagnostics;
using System.Reflection;
using System.Windows.Forms;

using MyXaml;

namespace MyXaml.MxWorkflow
{
	/// <summary>
	/// Assigns a value to a target property.
	/// </summary>
	public class Set : Process
	{
		protected string property;
		protected string val;

		/// <summary>
		/// The property whose value to set.  Specified as an attribute in the markup.
		/// </summary>
		public String Property
		{
			get {return property;}
			set {property=value;}
		}

		/// <summary>
		/// The value to which to set the property.  Specified as an attribute in the markup.
		/// </summary>
		public String Value
		{
			get {return val;}
			set {val=value;}
		}

		/// <summary>
		/// Internal use.
		/// </summary>
		/// <returns></returns>
		public override string ToString()
		{
			return "Set: "+property+"="+val;
		}

		/// <summary>
		/// Constructor.
		/// Used in the markup to instantiate a Set workflow.
		/// </summary>
		public Set()
		{
			target=String.Empty;
			property=String.Empty;
		}

		/// <summary>
		/// Internal use.  Processes the Set statement.
		/// </summary>
		/// <param name="wfProc"></param>
		public override void Invoke(MxWorkflowProcessor wfProc)
		{
			// Check to see if the container we are trying to set
			// the property for is nested
			// i.e model.container
			// Modifed 24/10/2004 Michael Butler

			object tempTarget=target;

			if(target != null && target is string)
			{
				string tg = target.ToString();
				if(tg[0] == '*')
				{
					tempTarget = this.LateBinding(tg);
				}
			}

			if ( (tempTarget != null) && (val != null) && (property != null) )
			{
				// get the target type (must be specified in the markup.
				Type t=tempTarget.GetType();
				object[] parms=new object[] {val};
				// process any late binding in the parameter.
				Type[] types=ProcessParams(parms);

				// get the property info for the specified property.
				PropertyInfo pi=t.GetProperty(property);
				if (pi != null)
				{
					try
					{
						object obj=parms[0];

						// get the TypeConverter for the property type.
						TypeConverter tc = TypeDescriptor.GetConverter(pi.PropertyType);

						// if the value is a string...
						if (obj is String)
						{
							// can we convert from a string to the property type
							if (tc != null && tc.CanConvertFrom(typeof(string)))
							{
								// changed from ConvertFromString, as per CPian tditiecher, to support different culture formats
								object objConv=null;
								try
								{
									objConv = tc.ConvertFromInvariantString((string)obj);
								}
								catch (Exception e)
								{
									Trace.WriteLine("Conversion from '"+val+"' failed: "+e.Message);
								}

								// The Form.MainMenu property returns true for CanConvertFrom, but null when the conversion takes place!
								if (objConv != null)
								{
									try
									{
										pi.SetValue(tempTarget, objConv, null);
									}
									catch(Exception e)
									{
										Trace.WriteLine("Workflow setter failed: "+e.Message);
									}
								}
							}
						}
						else
						{

							// get the type converter for the current value object
							TypeConverter valTypeConverter=TypeDescriptor.GetConverter(obj.GetType());
							
							// can we convert to the type required by the property?
							if (valTypeConverter.CanConvertTo(pi.PropertyType))
							{
								// if so, do the conversion
								obj=valTypeConverter.ConvertTo(obj, pi.PropertyType);
							}
							pi.SetValue(tempTarget, obj, null);
						}
					}
					catch(Exception e)
					{
						Trace.WriteLine("Invocation Exception: "+e.Message+"   "+e.InnerException);
					}
				}
				else
				{
					Trace.WriteLine("No property defined: "+property);
				}
			}
			else
			{
				Trace.WriteLine("Set is missing the target, property, and/or value");
			}
		}
	}
}