PropertyCollection Class

Represents a collection of properties that can be added to DataColumn, DataSet, or DataTable.

Namespace: System.Data
Assembly: System.Data (in

public class PropertyCollection : Hashtable
/** @attribute SerializableAttribute() */ 
public class PropertyCollection extends Hashtable
public class PropertyCollection extends Hashtable

The PropertyCollection can be accessed through the ExtendedProperties property of the DataColumn, DataSet, or DataTable class.

Add custom properties to the DataColumn, DataSet, or DataTable objects through the PropertyCollection. For example, you may want to store the time of the object's creation for later comparison to another object.

The following example creates a timestamp value for a DataTable and adds it to the PropertyCollection.

private void AddTimeStamp()
    //Create a new DataTable.
    DataTable table = new DataTable("NewTable");

    //Get its PropertyCollection.
    PropertyCollection properties = table.ExtendedProperties;

    //Add a timestamp value to the PropertyCollection.
    properties.Add("TimeStamp", DateTime.Now);

    // Print the timestamp.


Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0