ColumnAttribute.IsVersion Property

Reference

Definition

Namespace:: System.Data.Linq.Mapping

Assembly:: System.Data.Linq.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Gets or sets whether the column type of the member is a database timestamp or version number.

public:
 property bool IsVersion { bool get(); void set(bool value); };

public bool IsVersion { get; set; }

member this.IsVersion : bool with get, set

Public Property IsVersion As Boolean

Property Value

Boolean

Default value = false.

Examples

[Column(Storage = "_VersionNum", DbType = "Int NOT NULL IDENTITY", IsVersion=true)]
public int VersionNum
{
    get
    {
        return this._VersionNum;
    }

    set
    {
        if ((this._VersionNum != value))
        {
            this._VersionNum = value;
        }
    }
}

   <Column(Storage:="_VersionNum", DbType:="Int NOT NULL IDENTITY", IsVersion:=True)> _
Public Property VersionNum() As Integer
       Get
           Return Me._VersionNum
       End Get
       Set(ByVal value As Integer)
           If ((Me._VersionNum = value) _
              = False) Then
               Me._EmployeeID = value
           End If
       End Set
   End Property

Remarks

Version numbers are incremented and timestamp columns are updated every time that the associated row is updated. (This property tells LINQ to SQL that a column should be updated to show that it is a new version; it is not meant to record information such as who made the update.)

Note the following when IsVersion is true:

Use DbType to specify the correct modifiers to designate a version number or timestamp column. If you do not specify DbType, LINQ to SQL infers the correct modifiers.

Version numbers are incremented and timestamp columns are updated every time that the associated row is updated. Members with IsVersion=true are synchronized immediately after the data row is updated. The new values are visible after SubmitChanges finishes.

Applies to

Share via