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ChangeReason Enumeration

Provides the reason that the original data was restored to a ListObject that is bound to data.

Namespace:  Microsoft.Office.Tools.Excel
Assembly:  Microsoft.Office.Tools.Excel (in Microsoft.Office.Tools.Excel.dll)

Syntax

'Declaration
Public Enumeration ChangeReason
public enum ChangeReason

Members

Member name Description
DataBoundColumnHeaderIsAutoSet When the AutoSetDataBoundColumnHeaders property of the ListObject control is set to true, the ListObject control does not allow the user to change the column headers.
ErrorInCommit A change to data in the ListObject control could not be committed to the data source that the control is bound to.
FixedLengthDataSource The data source that the ListObject control is bound to does not allow adding or removing rows.
FixedNumberOfColumnsInDataBoundList The ListObject control does not allow columns to be added or removed after it is bound to data.
Other The original data was restored because of a reason not specified by any of the other ChangeReason values.
ReadOnlyDataSource The data source that the ListObject control is bound to is read-only.

Remarks

When the ListObject is bound to data and the user performs an operation that is not allowed, the ListObject restores itself to its previous state and raises the OriginalDataRestored event. The ChangeReason enumeration provides information about why this restoration occurred.

Examples

The following code example creates a DataTable and a ListObject, and binds the ListObject to the DataTable. It then creates an OriginalDataRestored event handler. To test the event, right-click a column letter above the ListObject on sheet 1 and then click Delete in the shortcut menu. The event handler replaces the column and column header data and displays a message indicating what kind of data was restored and the reason that the original data was restored.

This example is for a document-level customization.

WithEvents OriginalDataRestoredList As _
        Microsoft.Office.Tools.Excel.ListObject
    Private Sub ListObject_OriginalDataRestored()
        ' Create a new DataSet and DataTable. 
        Dim ds As New DataSet()
        Dim dt As DataTable = ds.Tables.Add("Customers")
        Dim lastName As New DataColumn("LastName")
        dt.Columns.Add(lastName)
        dt.Columns.Add(New DataColumn("FirstName"))

        ' Add two new rows to the DataTable. 
        Dim dr1 As DataRow = dt.NewRow()
        dr1("LastName") = "Chan"
        dr1("FirstName") = "Gareth"
        dt.Rows.Add(dr1)
        Dim dr2 As DataRow = dt.NewRow()
        dr2("LastName") = "Nitsche"
        dr2("FirstName") = "Sonja"
        dt.Rows.Add(dr2)

        ' Create a list object.
        OriginalDataRestoredList = Me.Controls.AddListObject( _
            Me.Range("A1"), "OriginalDataRestoredList")

        ' Bind the list object to the DataTable.
        OriginalDataRestoredList.AutoSetDataBoundColumnHeaders = True
        OriginalDataRestoredList.SetDataBinding(ds, "Customers", _
            "LastName", "FirstName")
    End Sub 

    Private Sub List1_OriginalDataRestored(ByVal sender As Object, _
        ByVal e As Microsoft.Office.Tools.Excel.OriginalDataRestoredEventArgs) _
        Handles OriginalDataRestoredList.OriginalDataRestored
        MessageBox.Show("This data is bound to a data source and " & _
        "will be restored. This change is: " & e.ChangeType.ToString() & _
        ". The reason is: " & e.ChangeReason.ToString() + ".")
    End Sub
private void ListObject_OriginalDataRestored()
{
    // Create a new DataSet and DataTable.
    DataSet ds = new DataSet();
    DataTable dt = ds.Tables.Add("Customers");
    DataColumn lastName = new DataColumn("LastName");
    dt.Columns.Add(lastName);
    dt.Columns.Add(new DataColumn("FirstName"));

    // Add two new rows to the DataTable.
    DataRow dr1 = dt.NewRow();
    dr1["LastName"] = "Chan";
    dr1["FirstName"] = "Gareth";
    dt.Rows.Add(dr1);
    DataRow dr2 = dt.NewRow();
    dr2["LastName"] = "Nitsche";
    dr2["FirstName"] = "Sonja";
    dt.Rows.Add(dr2);

    // Create a list object.
    Microsoft.Office.Tools.Excel.ListObject list1 = 
        this.Controls.AddListObject(
        this.Range["A1"], "list1");

    // Bind the list object to the DataTable.
    list1.AutoSetDataBoundColumnHeaders = true;
    list1.SetDataBinding(ds, "Customers", "LastName",
        "FirstName");

    // Create the event handler.
    list1.OriginalDataRestored += new 
        Microsoft.Office.Tools.Excel.
        OriginalDataRestoredEventHandler(list1_OriginalDataRestored);
}

void list1_OriginalDataRestored(object sender, 
    Microsoft.Office.Tools.Excel.OriginalDataRestoredEventArgs e)
{
    MessageBox.Show("This data is bound to a data source and " +
    "will be restored. This change is: " + e.ChangeType.ToString() +
    ". The reason is: " + e.ChangeReason.ToString() + ".");
}

See Also

Reference

Microsoft.Office.Tools.Excel Namespace