Manual Insert/Update Operations

Extracting values

There are two ways to extract the values from the item. From the item itself (ExtractValues) or through the RadTreeList control (ExtractValuesFromItem).

C#

item.ExtractValues(table);

VB

item.ExtractValues(table)

C#

RadTreeList1.ExtractValuesFromItem(table, item, true);

VB

RadTreeList1.ExtractValuesFromItem(table, item, True)

The syntax of the ExtractValuesFromItem method is as follows:

 

	ExtractValuesFromItem(IDictionary newValues, TreeListEditableItem dataItem, bool includePrimaryKey)
newValues	IDictionary collection that will be populated with the values extracted from the given item
dataItem	The item that will be used to extract the values from
includePrimaryKey	Determines whether the primary key will be extracted and added to the IDictionary collection

The ExtractValues method syntax is omitted as it is accepts only one object - the IDictionary collection that holds the extracted values.

Update

The update operation is nothing different compared to other databound controls like RadGrid.To perform this operation you will have to extract the edited values and then pass them to the corresponding datasource. This is an excerpt of our online demo:

C#

Hashtable table = new Hashtable();
TreeListEditableItem item = e.Item as TreeListEditableItem;
item.ExtractValues(table);

ConvertEmptyValuesToDBNull(table);

if (table["LastName"] != DBNull.Value && table["FirstName"] != DBNull.Value)
{
	string commandText = "UPDATE [Employees] SET [LastName] = @LastName, [FirstName] = @FirstName, [TitleOfCourtesy] = @TitleOfCourtesy, [ReportsTo] = @ReportsTo, [Notes] = @Notes WHERE [EmployeeID] = @EmployeeID";
	ExecuteNonQuery(commandText, table);
}

VB

Dim table As New Hashtable()
Dim item As TreeListEditableItem = TryCast(e.Item, TreeListEditableItem)
item.ExtractValues(table)

ConvertEmptyValuesToDBNull(table)

If Not table("LastName") Is DBNull.Value AndAlso Not table("FirstName") Is DBNull.Value Then
	Dim commandText As String = "UPDATE [Employees] SET [LastName] = @LastName, [FirstName] = @FirstName, [TitleOfCourtesy] = @TitleOfCourtesy, [ReportsTo] = @ReportsTo, [Notes] = @Notes WHERE [EmployeeID] = @EmployeeID"
	ExecuteNonQuery(commandText, table)
End If

Insert

Although the insert operation is generally the same as the update there is one peculiarity. If you are inserting a child item, the corresponding foreign key values will be extracted automatically from the parent item.This is not the case, however, when inserting new root item. In this case you have to manually insert a null (DbNull) value because the root item does not have a parent and this value should be populated by hand.

C#

Hashtable table = new Hashtable();
TreeListEditableItem item = e.Item as TreeListEditableItem;
#region treelist-manual-operations_1
item.ExtractValues(table);

VB

Dim table As New Hashtable()
Dim item As TreeListEditableItem = TryCast(e.Item, TreeListEditableItem)
' #region treelist-manual-operations_3
item.ExtractValues(table)

See Also

• TreeList / Manual data editing demo