"The code is exactly
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Module: modComboBox
Routines to extend the functionality of a standard VB ComboBox control.
Some of these procedures expose features which are inherent in the Windows control, but are not exposed by VB (such as the ability to set the drop-down list width).
Other procedures add entirely new functionality such as loading a DAO recordset into an unbound combo box.
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Procedure Name
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Type
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Description
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(Declarations)
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Declarations
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Declarations and private variables for the modComboBox module
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AddItemDataComboBox
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Procedure
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Adds an item to a combo box, and the itemdata value associated with that item, in a single function call
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ADORecordSetToComboBox
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Procedure
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Displays the contents of an ADO recordset in a standard unbound combo box.
You are responsible for creating a recordset object in your code and passing it to this subroutine. You can create a recordset based on an entire table, or you can limit the values by using a query or a SQL statement. You may designate one field in the recordset to display in the list box, and another field to store in the ItemData property.
Note that if you use a query to populate the combo box the display "field" can consist of a calculated expression, such as:
SELECT LastName & ", " & FirstName AS FullName, CustID From Customers
You could choose "FullName" as the display field and "CustID" as the key field to store in the ItemData property. Note that the value for the ItemData must be a storable in a Long Integer, so textual keys will not work.
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BinarySearchComboBox
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Procedure
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Use a binary search to find a value in a combo box.
A binary search works by dividing the values to be searched in half. If the search value is less than the value at the halfway point, then the top half is searched. If the value is greater than the value at the halfway point, then the bottom half is searched. This process is repeated until the value is either found, or no more values remain to be searched. This technique requires that the combobox be sorted.
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DropComboBoxList
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Procedure
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Causes a combo box to show or hide the list portion.
This function can be used to automatically drop down the list for a combo box when the user tabs into the combo box.
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FindStringComboBox
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Procedure
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Finds the line on a combo box containing the search string.
This function uses the Windows API SendMessage command to quickly find a string in a standard combo box control. You may search either for exact matches, or partial matches on the beginning of the combo box item.
Note that case is not considered in doing the search, even if the fExact argument is true.
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IncrementalSearchCombo
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Procedure
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Allows incremental searching of a combo box (on the KeyPress event of the ComboBox)
As the user types in the text portion of a combo box, this code finds the first item in the combo that matches the value that the user has typed so far. If a value is found, the contents of the combo box text field is replaced. The portion of the text that the user did not type is selected so that it is immediately replaced as the user continues typing.
This sub must be called from the KeyPress event of the combo box. Pass the KeyAscii argument of the KeyPress event directly through to the intKeyAscii argument.
The style property of the ComboBox must be "0 - Dropdown Combo" for this to work
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IsComboBoxDropped
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Procedure
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Determines if the list portion of a combo box is is currently visible
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RecordSetToComboBox
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Procedure
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Displays the contents of a recordset in a standard unbound combo box.
You are responsible for creating a recordset object in your code and passing it to this subroutine. You can create a recordset based on an entire table, or you can limit the values by using a query or a SQL statement. You may designate one field in the recordset to display in the list box, and another field to store in the ItemData property.
Note that if you use a query to populate the combo box the display "field" can consist of a calculated expression, such as:
SELECT LastName & ", " & FirstName AS FullName, CustID From Customers
You could choose "FullName" as the display field and "CustID" as the key field to store in the ItemData property. Note that the value for the ItemData must be a storable in a Long Integer, so textual keys will not work.
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SetComboBoxItemHeight
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Procedure
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Set the height of items in a combo box.
VB normally uses the standard height for items in a listbox based on the type and size of the font in the list box. Using Windows API calls you can specify a different height.
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SetComboBoxListItems
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Procedure
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Sets the number of items in the combo box list.
This procedure lets you change the number of items that are displayed in the drop-down list portion of a combo box. Windows normally shows a default number of items. By changing this value you can designate the number of items that you want to appear. This might be useful if you have a combo box that displays the months of the year, for example, and you want to have twelve items displayed on the list.
The number cannot be set to less than eight, or the actual number of items on the list, whichever is less.
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SetComboBoxListWidth
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Procedure
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Set the width of the drop-down list portion of a combo box.
Using the standard VB Combo Box control, the drop-down list portion of the combo box is always the same width as the combo box itself. Using this procedure you can specify that the list portion is wider than the actual combo box.
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