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DataRowVersion Enum

  • Reference

Definition

Namespace:
System.Data
Assembly:
System.Data.Common.dll
Assembly:
System.Data.dll
Assembly:
netstandard.dll

Describes the version of a DataRow.

public enum class DataRowVersion
public enum DataRowVersion
type DataRowVersion = 
Public Enum DataRowVersion
Inheritance
Object
ValueType
Enum
DataRowVersion

Fields

Name Value Description
Original 256

The row contains its original values.
Current 512

The row contains current values.
Proposed 1024

The row contains a proposed value.
Default 1536

The default version of DataRowState. For a DataRowState value of Added, Modified or Deleted, the default version is Current. For a DataRowState value of Detached, the version is Proposed.

Examples

The following example checks the DataRowVersion of a DataRow before invoking the AcceptChanges method.

private static void CheckVersionBeforeAccept()
{
    //Run a function to create a DataTable with one column.
    DataTable dataTable = MakeTable();

    DataRow dataRow = dataTable.NewRow();
    dataRow["FirstName"] = "Marcy";
    dataTable.Rows.Add(dataRow);

    dataRow.BeginEdit();
    // Edit data but keep the same value.
    dataRow[0] = "Marcy";
    // Uncomment the following line to add a new value.
    // dataRow(0) = "Richard"
    Console.WriteLine(string.Format("FirstName {0}", dataRow[0]));

    // Compare the proposed version with the current.
    if (dataRow.HasVersion(DataRowVersion.Proposed)) {
        if (object.ReferenceEquals(dataRow[0, DataRowVersion.Current], dataRow[0, DataRowVersion.Proposed])) {
            Console.WriteLine("The original and the proposed are the same.");
            dataRow.CancelEdit();
        } else {
            dataRow.AcceptChanges();
            Console.WriteLine("The original and the proposed are different.");
        }
    }
}

private static DataTable MakeTable()
{
    // Make a simple table with one column.
    DataTable dt = new DataTable("dataTable");
    DataColumn firstName = new DataColumn("FirstName", Type.GetType("System.String"));
    dt.Columns.Add(firstName);
    return dt;
}

Private Sub CheckVersionBeforeAccept()
    'Run a function to create a DataTable with one column.
    Dim dataTable As DataTable = MakeTable()

    Dim dataRow As DataRow = dataTable.NewRow()
    dataRow("FirstName") = "Marcy"
    dataTable.Rows.Add(dataRow)

    dataRow.BeginEdit()
    ' Edit data but keep the same value.
    dataRow(0) = "Marcy"
    ' Uncomment the following line to add a new value.
    ' dataRow(0) = "Richard"
    Console.WriteLine(String.Format("FirstName {0}", dataRow(0)))

    ' Compare the proposed version with the current.
    If dataRow.HasVersion(DataRowVersion.Proposed) Then
        If dataRow(0, DataRowVersion.Current) Is dataRow(0, DataRowVersion.Proposed) Then
            Console.WriteLine("The original and the proposed are the same.")
            dataRow.CancelEdit()
        Else
            dataRow.AcceptChanges()
            Console.WriteLine("The original and the proposed are different.")
        End If
    End If
End Sub

Private Function MakeTable() As DataTable
    ' Make a simple table with one column.
    Dim dt As New DataTable("dataTable")
    Dim firstName As New DataColumn("FirstName", _
       Type.GetType("System.String"))
    dt.Columns.Add(firstName)
    Return dt
End Function

Remarks

The DataRowVersion values are used when retrieving the value found in a DataRow using Item[] or the GetChildRows of the DataRow object.

The DataRowVersion informs you what version of a DataRow exists. Versions change under the following circumstances:

  • After calling the DataRow object's BeginEdit method, if you change the value, the Current and Proposed values become available.

  • After calling the DataRow object's CancelEdit method, the Proposed value is deleted.

  • After calling the DataRow object's EndEdit method, the Proposed value becomes the Current value.

  • After calling the DataRow object's AcceptChanges method, the Original value becomes identical to the Current value.

  • After calling the DataTable object's AcceptChanges method, the Original value becomes identical to the Current value.

  • After calling the DataRow object's RejectChanges method, the Proposed value is discarded, and the version becomes Current.

Applies to

See also