Sunday, July 08, 2007

/// <summary>
/// Provides a type converter to convert <see cref="T:System.Type"/> objects to and from various other representations.
/// </summary>
public class TypeTypeConverter : System.ComponentModel.TypeConverter
{
    /// <summary>
    /// Returns whether this converter can convert an object of the given type to the type of this converter, using the specified context.
    /// </summary>
    /// <param name="context">An <see cref="T:System.ComponentModel.ITypeDescriptorContext"></see> that provides a format context.</param>
    /// <param name="sourceType">A <see cref="T:System.Type"></see> that represents the type you want to convert from.</param>
    /// <returns>
    /// true if this converter can perform the conversion; otherwise, false.
    /// </returns>
    public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
    {
        return ((sourceType == typeof(string)) || base.CanConvertFrom(context, sourceType));
    }

    /// <summary>
    /// Converts from.
    /// </summary>
    /// <param name="context">The context.</param>
    /// <param name="culture">The culture.</param>
    /// <param name="value">The value.</param>
    /// <returns></returns>
    public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
    {
        if (value is string)
        {
            Type type = Type.GetType((string)value);
            if (type == null)
            {
                throw new ArgumentException("Type not found.", "value");
            }
            return type;
        }
        return base.ConvertFrom(context, culture, value);
    }

    /// <summary>
    /// Returns whether this converter can convert the object to the specified type, using the specified context.
    /// </summary>
    /// <param name="context">An <see cref="T:System.ComponentModel.ITypeDescriptorContext"></see> that provides a format context.</param>
    /// <param name="destinationType">A <see cref="T:System.Type"></see> that represents the type you want to convert to.</param>
    /// <returns>
    /// true if this converter can perform the conversion; otherwise, false.
    /// </returns>
    public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
    {
        return ((destinationType == typeof(string)) || base.CanConvertTo(context, destinationType));
    }

    /// <summary>
    /// Converts to.
    /// </summary>
    /// <param name="context">The context.</param>
    /// <param name="culture">The culture.</param>
    /// <param name="value">The value.</param>
    /// <param name="destinationType">Type of the destination.</param>
    /// <returns></returns>
    public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
    {
        if (destinationType != typeof(string))
        {
            return base.ConvertTo(context, culture, value, destinationType);
        }
        return ((Type)value).AssemblyQualifiedName;
    }
}