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SqlDataSourceView.ConflictDetection Property

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Gets or sets the value indicating how the SqlDataSource control performs updates and deletes when data in a row in the underlying database changes during the time of the operation.

public:
 property System::Web::UI::ConflictOptions ConflictDetection { System::Web::UI::ConflictOptions get(); void set(System::Web::UI::ConflictOptions value); };
public System.Web.UI.ConflictOptions ConflictDetection { get; set; }
member this.ConflictDetection : System.Web.UI.ConflictOptions with get, set
Public Property ConflictDetection As ConflictOptions

Property Value

ConflictOptions

One of the ConflictOptions values. The default is the OverwriteChanges value.

Exceptions

ArgumentOutOfRangeException

The selected value is not one of the ConflictOptions values.

Remarks

The ConflictDetection property determines whether parameters for old and new values are applied to the Update method. For example, if the command that is specified by the SelectCommand property returns a DataSet object with the columns Name and Number, and the ConflictDetection property is set to the OverwriteChanges value, parameters are created for Name and Number for the update operation. If the ConflictDetection property is set to the CompareAllValues value, parameters are created for Name, Number, original_Name, and original_Number. (The exact name of the parameters for the original values depends on the OldValuesParameterFormatString.) Then, the SqlDataSourceView object determines if the method that is specified in the UpdateCommand property has parameters that match.

Concurrency control is a technique data stores use to control how data is read and changed in the store when multiple clients are accessing and manipulating the same data. For example, one client reads data and presents it to a user, while another client reads the same data, and presents it to a different user. If both users update the data and submit it to the data storage, some unexpected result might occur, because both clients might update different values for the same data. This is considered a conflict. By setting the ConflictDetection property to the CompareAllValues value, the update operation can then compare the old and new values to the original data source to detect conflicts and handle them as required.

The value of the ConflictDetection property is stored in view state.

Applies to

See also