DataKey Class
Represents the primary key field or fields of a record in a data-bound control.
Assembly: System.Web (in System.Web.dll)
The DataKey type exposes the following members.
| Name | Description | |
|---|---|---|
![]() | DataKey(IOrderedDictionary) | Initializes a new instance of the DataKey class using the specified dictionary of key field values. |
![]() | DataKey(IOrderedDictionary, array<String>) | Initializes a new instance of the DataKey class using the specified dictionary of key field values and array of field names. |
| Name | Description | |
|---|---|---|
![]() | IsTrackingViewState | Gets a value indicating whether the DataKey object is tracking its view-state changes. |
![]() | Item[Int32] | Gets the value of the key field at the specified index from a DataKey object. |
![]() | Item[String] | Gets the value of the key field with the specified field name from a DataKey object. |
![]() | Value | Gets the value of the key field at index 0 in the DataKey object. |
![]() | Values | Gets an IOrderedDictionary object that contains every key field in the DataKey object. |
| Name | Description | |
|---|---|---|
![]() | Equals(DataKey) | Determines whether the specified DataKey array is equal to the current data key. |
![]() | Equals(Object) | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
![]() | Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
![]() | GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
![]() | GetType | Gets the Type of the current instance. (Inherited from Object.) |
![]() | LoadViewState | Loads the previously saved view state of the DataKey object. |
![]() | MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
![]() | SaveViewState | Saves the current view state of the DataKey object. |
![]() | ToString | Returns a string that represents the current object. (Inherited from Object.) |
![]() | TrackViewState | Marks the starting point at which to begin tracking and saving view-state changes to the DataKey object. |
| Name | Description | |
|---|---|---|
![]() ![]() | IStateManager::IsTrackingViewState | Gets a value indicating whether the DataKey object is tracking its view-state changes. |
![]() ![]() | IStateManager::LoadViewState | Infrastructure. Loads the previously saved view state of the DataKey object. |
![]() ![]() | IStateManager::SaveViewState | Infrastructure. Saves the current view state of the DataKey object. |
![]() ![]() | IStateManager::TrackViewState | Infrastructure. Marks the starting point at which to begin tracking and saving view-state changes to the DataKey object. |
The DataKey class is used to represent the primary key for a record in a data-bound control. The primary key for a record can be composed of one of more fields from the data source. Although the DataKey class is not a collection, it can store multiple key field values. The key field values are populated when one of the constructors for the DataKey class is called. You can retrieve a key field value from a DataKey object in the following ways:
Use the DataKey::Item[Int32] property to retrieve a key field value at a specific index in the DataKey object.
Use the DataKey::Item[String] property to retrieve a key field value of a specific field.
Use the Value property to retrieve the value of the key field at index 0 in the DataKey object. This property is often used as a shortcut to retrieve the key value of a record when the primary key contains only one field.
Use the Values property to create an IOrderedDictionary object that can be used to iterate through the key field values.
In general, DataKey objects are automatically generated by data-bound controls when the control's DataKeyNames property is set. The DataKey objects contain the values of the key field or fields specified in the DataKeyNames property. Data-bound controls that display a single record at a time (such as DetailsView or FormView) generally store the DataKey object for the current record displayed in the DataKey property of the control. Data-bound controls that display multiple records at a time (such as GridView) generally store the DataKey objects for each record in the control in a DataKeyArray collection. The DataKeyArray collection is then stored in the DataKeys property of the control.
The following code example demonstrates how to determine the primary key value of a record in a DetailsView control using the Value property of a DataKey object.
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.






