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A simple lesson using type converters

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A simple lesson using type converters

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I found myself writing the following code this evening:

public T GetItem<T>(string name)
{
  string result = node.SelectSingleNode(name).InnerText.Trim();

  return (T)GetConverter(typeof(T)).ConvertFromString(result);
}

private TypeConverter GetConverter(Type objectType)
{
  if (objectType.Equals(typeof(int)))
    return new Int32Converter();
  else if (objectType.Equals(typeof(bool)))
    return new BooleanConverter();
  else if (objectType.Equals(typeof(string)))
    return new StringConverter();
  else
    throw new ArgumentException("Does not support casting to " + objectType.Name);
}

Don’t ever write code like this. Read the documentation which explicitly says that “you should never create an instance of a BooleanConverter”. If you follow their advice, your code will become much cleaner. Like so:

public T GetItem<T>(string name)
{
  string result = node.SelectSingleNode(name).InnerText.Trim();
  return (T)TypeDescriptor.GetConverter(typeof(T)).ConvertFromString(result);
}