Question

I’m currently working on an application where I need to load data from an SQL database and then assign the retrieved values into the properties of an object. I’m doing this by using reflection since the property names and column names are the same. However, many of the properties are using a custom struct type that is basically a currency wrapper for the decimal type. I have defined an implicit conversion in my struct:

public static implicit operator Currency(decimal d)
{
     return new Currency(d);
}

This works fine when I use it in code. However, when I have this:

foreach (PropertyInfo p in props)
{
     p.SetValue(this, table.Rows[0][p.Name], null);
}

It throws an ArgumentException stating that it cannot convert from System.Decimal to Currency. I’m confused since it works fine in any other circumstance.

Answer 1

I think you need to first unbox the value in table.Rows[0][p.Name] as a decimal.

In other words:

foreach (PropertyInfo p in props)
{
     if (p.PropertyType == typeof(Currency))
     {
         Currency c = (decimal)table.Rows[0][p.Name];
         p.SetValue(this, c, null);
     }
     else
     {
         p.SetValue(this, table.Rows[0][p.Name], null);
     }
}

This is an issue I’ve seen once or twice before, so I actually decided to write a blog post about it. Anybody looking for a little more explanation, feel free to give it a read.