Question

According to MySql in this document C.7.9.6. Changes in MySQL Connector/NET 5.0.5 (07 March 2007):

Added MySqlParameterCollection.AddWithValue and marked the Add(name, value) method as obsolete.

I’ve been using .Add up until recently and experienced no problems. Upon discovering the .AddWithValue method, it is preferable primarily because it involves less syntax.

My question: does anyone know if there is any functional difference between the two methods? I cannot find proper documentation on them.

Edit:

Microsoft makes this note about SqlParameterCollection:

AddWithValue replaces the
SqlParameterCollection.Add method that
takes a String and an Object. The
overload of Add that takes a string
and an object was deprecated because
of possible ambiguity with the
SqlParameterCollection.Add overload
that takes a String and a SqlDbType
enumeration value where passing an
integer with the string could be
interpreted as being either the
parameter value or the corresponding
SqlDbType value. Use AddWithValue
whenever you want to add a parameter
by specifying its name and value.

Perhaps it is for the same reason.

Answer 1

When the documentation says nothing, consult the source.
These methods are identical (in their implementation):

/// <summary>
/// Adds a <see cref="MySqlParameter"/> to the <see cref="MySqlParameterCollection"/> given the specified parameter name and value.
/// </summary>
/// <param name="parameterName">The name of the parameter.</param>
/// <param name="value">The <see cref="MySqlParameter.Value"/> of the <see cref="MySqlParameter"/> to add to the collection.</param>
/// <returns>The newly added <see cref="MySqlParameter"/> object.</returns>
[Obsolete("Add(String parameterName, Object value) has been deprecated.  Use AddWithValue(String parameterName, Object value)")]
public MySqlParameter Add(string parameterName, object value)
{
    return Add(new MySqlParameter(parameterName, value));
}

public MySqlParameter AddWithValue(string parameterName, object value)
{
    return Add(new MySqlParameter(parameterName, value));
}

http://mysql-connector-net-5.0.sourcearchive.com/documentation/5.0.8.1/parameter__collection_8cs-source.html