Cinchoo – ChoObject.ToString(), Part 10

Defining and using TypeConverter

Sometime you may want to customize the object member string represent. One way of achieving it by creating TypeConverter or existing .NET type converters and using them.

Defining TypeConverter

public class ChoArrayToStringConverter : TypeConverter
{
    public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
    {
        if (destinationType == typeof(string))
            return true;
        else
            return base.CanConvertTo(context, destinationType);
    }

    public override object ConvertTo(ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value, Type destinationType)
    {
        if (value == null)
            return null;

        StringBuilder msg = new StringBuilder();
        if (value.GetType().IsArray)
        {
            foreach (object item in (Array)value)
            {
                if (msg.Length == 0)
                    msg.Append(ChoString.ToString(item, String.Empty, String.Empty));
                else
                    msg.AppendFormat(", {0}", ChoString.ToString(item, String.Empty, String.Empty));
            }
            return msg.ToString();
        }
        return base.ConvertFrom(context, culture, value);
    }
}

Using TypeConverter

[ChoTypeFormatter("'{this.Name}' Security State")]
public class Portfolio : ChoObject
{
    public string Name;
    public string Description;
    [ChoMemberFormatter(TypeConverter = typeof(ChoArrayToStringConverter))]
    public string[] Securities;
    [ChoMemberFormatter(TypeConverter = typeof(BooleanConverter))]
    public bool Live;

    public Portfolio(string name, string description, string[] securities)
    {
        Name = name;
        Description = description;
        Securities = securities;
    }
}

static void Main(string[] args)
{
    try
    {
        Portfolio portfolio = new Portfolio("High-Growth", "High Growth Portfolio", new string[] { "AAPL", "GOOG", "IBM" });
        Console.WriteLine(portfolio.ToString());
    }
    finally
    {
        ChoAppDomain.Exit();
    }
}

The output will be

-- 'High-Growth' Security State --
        Name: High-Growth
        Description: High Growth Portfolio
        Securities: AAPL, GOOG, IBM
        Live: False

Press any key to continue . . .

Happy coding!!!