/// <summary>
/// Populates the properties of an object from a single DataReader row using
/// Reflection by matching the DataReader fields to a public property on
/// the object passed in. Unmatched properties are left unchanged.
///
/// You need to pass in a data reader located on the active row you want
/// to serialize.
///
/// This routine works best for matching pure data entities and should
/// be used only in low volume environments where retrieval speed is not
/// critical due to its use of Reflection.
/// </summary>
/// <param name="reader">Instance of the DataReader to read data from. Should be located on the correct record (Read() should have been called on it before calling this method)</param>
/// <param name="instance">Instance of the object to populate properties on</param>
/// <param name="fieldsToSkip">Optional - A comma delimited list of object properties that should not be updated</param>
/// <param name="piList">Optional - Cached PropertyInfo dictionary that holds property info data for this object</param>
public static void DataReaderToObject(this IDataReader reader, ref object instance, Type type = null, string fieldsToSkip = null, Dictionary <string, PropertyInfo> piList = null)
{
if (reader.IsClosed)
{
throw new InvalidOperationException("Data reader cannot be used because it's already closed");
}
var _type = instance == null ? type : instance.GetType();
if (_type.IsNullableOrBasicType())
{
var value = reader[0];
if (value != null && !DBNull.Value.Equals(value))
{
if (_type == TypeHelper.TypeOfString)
{
instance = Activator.CreateInstance(TypeHelper.TypeOfString, SafeClrConvert.ToString(value).ToCharArray());
}
else
{
instance = SafeClrConvert.ChangeType(value, _type);
}
}
return;
}
if (string.IsNullOrEmpty(fieldsToSkip))
{
fieldsToSkip = string.Empty;
}
else
{
fieldsToSkip = "," + fieldsToSkip + ",";
}
fieldsToSkip = fieldsToSkip.ToLower();
// create a dictionary of properties to look up
// we can pass this in so we can cache the list once
// for a list operation
if (piList == null)
{
piList = new Dictionary <string, PropertyInfo>();
var props = _type.GetProperties(BindingFlags.Instance | BindingFlags.Public);
foreach (var prop in props)
{
piList.Add(prop.Name.ToLower(), prop);
}
}
for (var index = 0; index < reader.FieldCount; index++)
{
var name = reader.GetName(index).ToLower();
if (piList.ContainsKey(name))
{
var prop = piList[name];
if (fieldsToSkip.Contains("," + name + ","))
{
continue;
}
if ((prop != null) && prop.CanWrite)
{
var val = reader.GetValue(index);
prop.SetValue(instance, (val == DBNull.Value) ? null : val, null);
}
}
}
}