dddw.property

Description

Properties that control the appearance and behavior of a column with the DropDownDataWindow edit style.

Applies to

Column controls

Syntax

DataWindow .NET dot notation:

(( DDDW) colname.EditStyle).property [C#]
CType(colname.EditStyle, DDDW).property [Visual Basic]

Describe and Modify argument:

"columnname.dddw.property { = value }"

Parameter	Description
columnname	The name of a column that has the DropDownDataWindow edit style.
property	A property for the DropDownDataWindow column. Properties and their settings are listed in the table below.
value	The value to be assigned to the property. For dddw properties, value cannot be a DataWindow expression.

Property for dddw	Value
AllowEdit	Whether the user can type a value as well as choose from the DropDownDataWindow’s list. Values are: Yes – Typing is allowed. No – (Default) Typing is not allowed. Call GetChild after setting dddw.AllowEdit to get a valid reference to the column’s DropDownDataWindow.
AutoHScroll	Whether the DropDownDataWindow automatically scrolls horizontally when the user enters or deletes data. Values are: Yes – (Default) Scroll horizontally automatically. No – Do not scroll automatically.
AutoRetrieve	Whether the DropDownDataWindow data is retrieved when the parent DataWindow data is retrieved. Values are: Yes – (Default) Data is automatically retrieved. No – Data must be retrieved separately.
Case	The case of the text in the DropDownDataWindow. Values are: Any – Character of any case allowed. Upper – Characters converted to uppercase. Lower – Characters converted to lowercase. Call GetChild after setting dddw.Case to get a valid reference to the column’s DropDownDataWindow.
DataColumn	A string whose value is the name of the data column in the associated DropDownDataWindow. Value is quoted. Call GetChild after setting dddw.DataColumn to get a valid reference to the column’s DropDownDataWindow.
DisplayColumn	A string whose value is the name of the display column in the associated DropDownDataWindow. Value is quoted. Call GetChild after setting dddw.DisplayColumn to get a valid reference to the column’s DropDownDataWindow.
HScrollBar	Whether a horizontal scroll bar displays in the DropDownDataWindow. Values are: Yes – Display a horizontal scroll bar. No – Do not display a horizontal scroll bar.
HSplitScroll	Whether the horizontal scroll bar is split. The user can adjust the split position. Values are: Yes – Split the horizontal scroll bar so the user can scroll the display and data columns separately. No – The horizontal scroll bar is not split.
Limit	An integer from 0 to 32767 specifying the maximum number of characters that can be entered in the DropDownDataWindow. Zero means unlimited.
Lines	An integer from 0 to 32767 specifying the number of lines (values) to display in the DropDownDataWindow. This property does not apply in Web pages because the browser controls how the DropDownDataWindow displays.
Name	A string whose value is the name of the DropDownDataWindow associated with the column. Call GetChild after setting dddw.Name to get a valid reference to the column’s DropDownDataWindow.
NilIsNull	Whether to set the data value of the DropDownDataWindow to null when the user leaves the edit box blank. Values are: Yes – Make the Empty string null. No – Do not make the empty string null.
PercentWidth	An integer specifying the width of the drop-down portion of the DropDownDataWindow as a percentage of the column’s width. For example, 300 sets the display width to three times the column width. Call GetChild after setting dddw.PercentWidth to get a valid reference to the column’s DropDownDataWindow.
Required	Whether the column is required. Values are: Yes – Required. No – (Default) Not required.
ShowList	Whether the ListBox portion of the DropDownDataWindow displays when the column has focus. A down arrow does not display at the right end of the DropDownDataWindow when dddw.ShowList is yes. Values are: Yes – Display the list whenever the column has the focus. No – Do not display the list until the user selects the column.
UseAsBorder	Whether a down arrow displays at the right end of the DropDownDataWindow. Values are: Yes – Display the arrow. No – Do not display the arrow. Note that if ShowList is set to Yes, the column ignores the UseAsBorder property and the arrow never displays.
VScrollBar	Whether a vertical scroll bar displays in the DropDownDataWindow for long lists. Values are: Yes – Display a vertical scroll bar. No – Do not display a vertical scroll bar..

Usage

DropDownDataWindows and GetChild

When you set some of the dddw properties, as noted in the table, references to the DropDownDataWindow become invalid. Call GetChild again after changing these properties to obtain a valid reference.

To retrieve a DropDownDataWindow when the AutoRetrieve property is set to False, you can access the object data as follows:

[Visual Basic]
dw1.GetChild ("dept_head_id", mgr_id)

mgr_id.SetTransaction (SQLCA)

mgr_id.Retrieve ( )

You can also pass a retrieval argument for the retrieve on the child DataWindow object.

Doing a reset to clear the data

When a DropDownDataWindow is retrieved, its data is kept with its own Data Object. If you retrieve the DropDownDataWindow and then set the AutoRetrieve property on the parent to False, the data for the child is not cleared on a reset and re-retrieve of the parent.

To clear data from a DropDownDataWindow, you must call Reset on the child DataWindow object:

dw1.GetChild ("dept_head_id", mgr_id)

mgr_id.reset ( )

In the painter

Select the control and set values in the Properties window, Behavior category, when EditStyle is DropDownDW.

In DataWindow .NET, you can use the DDDW class to set DropDownDW style properties using dot notation. See the description of the DDDW class in the online Help in Visual Studio .NET for a complete list of properties. Some properties have different names and are set differently. For example, the Case DataWindow object property is equivalent to the CharacterCasing property in DataWindow .NET, which uses an enumeration.

Examples

Example 1

[Visual Basic]
ls_data = dw1.Describe("emp_status.dddw.AllowEdit")

dw1.Modify("emp_status.dddw.Case='Any'")

dw1.Modify("emp_status.dddw.DataColumn='status_id'")

dw1.Modify("emp_status.dddw.Limit=30")

dw1.Modify("emp_status.dddw.Name='d_status'")

dw1.Modify("emp_status.dddw.PercentWidth=120")

Example 2

[Visual Basic]
If TypeOf state.EditStyle Is DDDW Then
   CType(state.EditStyle, DDDW).AllowEdit = True
ElseIf
...

[C#]
if (state.EditStyle is DDDW)
{
   ((DDDW)state.EditStyle).AllowEdit = true;
}
else
....