SafeDispatch/Service Configurator/CustomClass.cs

using System;
using System.ComponentModel;
using System.Collections;

namespace ServiceConfigurator
{
    /// <summary>
    /// Modified class from the CustomClass originally created by Venu Madhav.
    /// Venu's DataTable and DataColumn objects have been removed and variables and
    /// class names have been renamed. The derived DynamicProperty class below now contains 
    /// the property data. This is a simpler implementation becuase the backing store for 
    /// the property data is the XML Config file - no need for another set of objects to hold 
    /// the data before it gets written back to the config file (although actually holding the
    /// property data in the PropertyDescriptor class is probably a little unorthodox).
    /// CustomClass implements ICustomTypeDescriptor and derives ExpandableObjectConverter.
    /// This class can be instantiated and properties to this class can
    /// be added dynamically using AddProperty(string propName, object propValue, string propDesc, 
    /// string propCat,  System.Type propType, bool isReadOnly, bool isExpandable). 
    /// </summary>

    [TypeConverter(typeof(ExpandableObjectConverter))]
    public partial class CustomClass : Component, ICustomTypeDescriptor
    {

        //Private members
        private PropertyDescriptorCollection propertyCollection;
        //Max length will be used help control the layout of the Windows Form and PropertyGrid
        //or the table of controls in an ASP.Net page. The Form or Webpage layout will be adjusted
        //dynamically depending on length of these values.
        private int _maxLength;
        public int MaxLength
        {
            get
            {
                return _maxLength;
            }
            set
            {
                if (value > _maxLength)
                    _maxLength = value;
            }
        }

        /// <summary>
        /// Constructor of CustomClass which initializes the new PropertyDescriptorCollection.
        /// </summary>
        public CustomClass()
        {
            propertyCollection = new PropertyDescriptorCollection(new PropertyDescriptor[] { });
        }


        /// <summary>
        /// Adds a property into the CustomClass.
        /// </summary>
        /// <param name="propName">Name of the property that needs to be added.</param>
        /// <param name="propValue">Value of the property that needs to be added.</param>
        /// <param name="propDesc">Description of the property that needs to be added.</param>
        /// <param name="propCat">The category to display this property in.</param>
        /// <param name="isReadOnly">Sets the property value to readonly in the property grid.</param>
        /// <param name="isExpandable">Tells the property grid that this property is expandable.</param>
        /// <param name="propType">DataType of the property that needs to be added.</param>
        public void AddProperty(string propName, object propValue, string propDesc,
            string propCat, System.Type propType, bool isReadOnly, bool isExpandable)
        {
            DynamicProperty p = new DynamicProperty(propName, propValue, propDesc, propCat,
                propType, isReadOnly, isExpandable);
            propertyCollection.Add(p);
            //Set our layout helper value.
            this.MaxLength = propName.Length;
            this.MaxLength = propValue.ToString().Length;
        }

        //Indexer for this class - returns a DynamicProperty by index position.
        public DynamicProperty this[int index]
        {
            get
            {
                return (DynamicProperty)propertyCollection[index];
            }
        }

        //Overloaded Indexer for this class - returns a DynamicProperty by name.
        public DynamicProperty this[string name]
        {
            get
            {
                return (DynamicProperty)propertyCollection[name];
            }
        }

        /// <summary>
        ///
        /// </summary>
        /// <returns></returns>
        public string GetClassName()
        {
            return (TypeDescriptor.GetClassName(this, true));
        }

        /// <summary>
        ///
        /// </summary>
        /// <returns></returns>
        public AttributeCollection GetAttributes()
        {
            return (TypeDescriptor.GetAttributes(this, true));
        }

        /// <summary>
        ///
        /// </summary>
        /// <returns></returns>
        public string GetComponentName()
        {
            return (TypeDescriptor.GetComponentName(this, true));
        }

        /// <summary>
        ///
        /// </summary>
        /// <returns></returns>
        public TypeConverter GetConverter()
        {
            return (TypeDescriptor.GetConverter(this, true));
        }

        /// <summary>
        ///
        /// </summary>
        /// <returns></returns>
        public EventDescriptor GetDefaultEvent()
        {
            return (TypeDescriptor.GetDefaultEvent(this, true));
        }

        /// <summary>
        ///
        /// </summary>
        /// <returns></returns>
        public PropertyDescriptor GetDefaultProperty()
        {
            PropertyDescriptorCollection props = GetAllProperties();

            if (props.Count > 0)
                return (props[0]);
            else
                return (null);
        }

        /// <summary>
        ///
        /// </summary>
        /// <param name="editorBaseType"></param>
        /// <returns></returns>
        public object GetEditor(Type editorBaseType)
        {
            return (TypeDescriptor.GetEditor(this, editorBaseType, true));
        }

        /// <summary>
        ///
        /// </summary>
        /// <param name="attributes"></param>
        /// <returns></returns>
        public EventDescriptorCollection GetEvents(Attribute[] attributes)
        {
            return (TypeDescriptor.GetEvents(this, attributes, true));
        }

        /// <summary>
        ///
        /// </summary>
        /// <returns></returns>
        public EventDescriptorCollection GetEvents()
        {
            return (TypeDescriptor.GetEvents(this, true));
        }

        /// <summary>
        ///
        /// </summary>
        /// <param name="attributes"></param>
        /// <returns></returns>
        public PropertyDescriptorCollection GetProperties(Attribute[] attributes)
        {
            return (GetAllProperties());
        }

        /// <summary>
        ///
        /// </summary>
        /// <returns></returns>
        public PropertyDescriptorCollection GetProperties()
        {
            return (GetAllProperties());
        }

        /// <summary>
        ///
        /// </summary>
        /// <param name="pd"></param>
        /// <returns></returns>
        public object GetPropertyOwner(PropertyDescriptor pd)
        {
            return (this);
        }


        /// <summary>
        ///	Helper method to return the PropertyDescriptorCollection or our Dynamic Properties
        /// </summary>
        /// <param name="pd"></param>
        /// <returns></returns>
        private PropertyDescriptorCollection GetAllProperties()
        {
            return propertyCollection;
        }



        /// <summary>
        ///	This is the Property class this will be dynamically added to the class at runtime.
        ///	These classes are returned in the PropertyDescriptorCollection of the GetAllProperties
        ///	method of the custom class.
        /// </summary>
        /// <param name="pd"></param>
        /// <returns></returns>
        public class DynamicProperty : PropertyDescriptor
        {
            private string propName;
            private object propValue;
            private string propDescription;
            private string propCategory;
            private Type propType;
            private bool isReadOnly;
            private bool isExpandable;

            public DynamicProperty(string pName, object pValue, string pDesc, string pCat, Type pType, bool readOnly, bool expandable)
                : base(pName, new Attribute[] { })
            {
                propName = pName;
                propValue = pValue;
                propDescription = pDesc;
                propCategory = pCat;
                propType = pType;
                isReadOnly = readOnly;
                isExpandable = expandable;
            }

            public override System.Type ComponentType
            {
                get
                {
                    return null;
                }
            }

            public override string Category
            {
                get
                {
                    return propCategory;
                }
            }

            public override bool IsReadOnly
            {
                get
                {
                    return isReadOnly;
                }
            }

            public override System.Type PropertyType
            {
                get
                {
                    return propType;
                }
            }

            public override bool CanResetValue(object component)
            {
                return true;
            }

            public override object GetValue(object component)
            {
                return propValue;
            }

            public override void SetValue(object component, object value)
            {
                propValue = value;
            }

            public override void ResetValue(object component)
            {
                propValue = null;
            }

            public override bool ShouldSerializeValue(object component)
            {
                return false;
            }

            public override string Description
            {
                get
                {
                    return propDescription;
                }
            }
        }
    }
}