Q157052: HOWTO: Display Blank in Place of .NULL. in a Grid Column

Article: Q157052
Product(s): Microsoft FoxPro
Version(s): 
Operating System(s): 
Keyword(s): kbnokeyword kbvfp300 kbvfp500 kbvfp600
Last Modified: 26-AUG-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 3.0, 3.0b, 5.0, 6.0 
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SUMMARY
=======

This article describes how to display a blank in place of .NULL. in a Grid
column in Visual FoxPro 3.0, and 3.0b.

MORE INFORMATION
================

By default, fields containing NULL values are displayed as .NULL. in a Grid in
all versions of Visual FoxPro. To display a blank in place of .NULL. in a column
of a grid in Visual FoxPro 3.0 and 3.0b, place an inline if (IIF) statement in
the DynamicForeColor property of the subject column. The IIF sets the column's
ForeColor to the same color as the Grid Column's BackColor when the field
contains a value. In Visual FoxPro 5.0 a NULL value can be displayed as a blank
in a Grid by issuing the following SET command, which makes setting the
DynamicForeColor unnecessary:

     SET NULLDISPLAY TO ''

Use the following steps to set the DynamicForeColor property of a column to white
when a field contains a NULL value and to black when the value is not NULL. This
article assumes that the Grid column's BackColor property is white (255,255,255)
and that the ForeColor property is black (0,0,0). This article also assumes a
working knowledge of creating forms, grids, and tables.

1. Create a table called Test.dbf with a numeric field named nNulltest, which
  allows null values.

2. Add some records to the table, storing .NULL. in the nNulltest field of some
  of the records.

3. Create a form.

4. Add the table Test.dbf, created above, to the DataEnvironment of the form.

5. Create a Grid on the form by dragging Test.dbf onto the form.

6. Change the Grid's ColumnCount property to 1.

7. Place the following in column 1's DynamicForeColor property:

        IIF(ISNULL(nNulltest),RGB(255,255,255),RGB(0,0,0))

  A true condition sets DynamicForeColor to white; a false condition is set to
  black.

8. Run the form. Notice that a blank instead of .NULL. appears in the rows of
  the Grid pertaining to records with a NULL value in the nNulltest field.
  Should you get an error message starting with "Error loading file," you can
  correct the problem by deleting the = (equal sign) placed at the beginning of
  your IIF statement in the DynamicForeColor property.

Additional query words:

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Keywords          : kbnokeyword kbvfp300 kbvfp500 kbvfp600 
Technology        : kbVFPsearch kbAudDeveloper kbVFP300 kbVFP300b kbVFP500 kbVFP600
Issue type        : kbhowto

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