PRB: SET CENTURY ROLLOVER Ignores Setting of SET CENTURY OFF

• Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a

SYMPTOMS

When using the ROLLOVER parameter of SET CENTURY, the SET CENTURY OFF setting is ignored. This results in a date display consisting of either two digits or four digits for the year portion of the date.

RESOLUTION

The reason for the display of the year in either a two or four-digit format is to differentiate which century the date belongs to.

It is possible to create a custom display format, which presents the date in the 'MM/DD/YY' format along with another field to display which century.

The following program demonstrates a sample method to do this.

Steps to Reproduce Solution

1. Save the following code as Daterev.prg:

         *** Begin code ***
         ON  KEY  LABEL f2 CLEAR EVENTS
         ON KEY LABEL f3 DO refresh
         SET CENTURY to 19 ROLLOVER 60
         SET CENTURY off
         dateform=CREATEOBJECT('form')
         WITH dateform
            .width=300
            .height=65
            .ADDOBJECT('text1','textbox')
            WITH .text1
               .format='K'
               .inputmask='99/99/99'
               .left=1
               .top=10
               .width=60
               .value=DTOC(date())
               .visible=.t.
            ENDWITH   && text1
            .ADDOBJECT('label1','label')
            WITH .label1
               .top=50
               .left=90
               .width=120
               .fontbold=.t.
               .caption="Press <F2> to exit form"
               .visible=.t.
            ENDWITH   && label1
            .ADDOBJECT('label2','label')
            WITH .label2
               .caption="Year of date shown is  "+ ;
                  ALLTRIM(STR(YEAR(CTOD(dateform.text1.value))))
               .top=32
               .left=10
               .width=160
               .fontbold=.t.
               .visible=.t.
            ENDWITH   && label2
            .ADDOBJECT('label3','label')
            WITH .label3
               .caption='Press <f3> to refresh after entering new date'
               .top=10
               .left=65
               .width=250
               .fontbold=.t.
               .visible=.t.
            ENDWITH   && label3
            .show
         ENDWITH   && dateform
         READ EVENTS
         ON KEY LABEL f2
         ON KEY LABEL f3
   
         PROCEDURE refresh
            dateform.label2.caption="Year of date shown is: "+ ;
                ALLTRIM(STR(YEAR(CTOD(dateform.text1.value))))
            dateform.refresh
         RETURN
         *** End code ***
   
   

2. Run the program. NOTE: The four-digit display of the date shown is shown below the text box.

3. Enter a valid date for the 21st century, such as "02/12/55."

4. Press F3 to refresh the display. NOTE: In the line below the text box, the year is shown as "2055."

STATUS

This behavior is by design.

MORE INFORMATION

The ROLLOVER clause of SET CENTURY command permits ease of entering dates, which may cross century boundaries, for example:

   SET CENTURY to 19 ROLLOVER 60

Using the information above, "02/15/97" is deemed the year "1997." And "02/15/55" is interpreted as the year 2055.

To better understand the implications of the ROLLOVER parameter, the following program demonstrates its effect on how dates are displayed.

Steps to Reproduce Behavior

1. Save the following code as Formdate.prg:

         *** Begin code ***
         ON  KEY  LABEL f2 CLEAR EVENTS
         SET CENTURY to 19 ROLLOVER 60
         SET CENTURY off
         dateform=CREATEOBJECT('form')
         WITH dateform
            .width=120
            .height=65
            .ADDOBJECT('text1','textbox')
            WITH .text1
               .format='K'
               .left=35
               .top=10
               .width=75
               .value=date()
               .visible=.t.
            ENDWITH   && text1
            .ADDOBJECT('label1','label')
            WITH .label1
               .top=35
               .left=1
               .width=120
               .fontbold=.t.
               .caption="Press <F2> to exit form"
               .visible=.t.
            ENDWITH   && label1
            .show
         ENDWITH   && dateform
         READ EVENTS
         ON KEY LABEL f2
         *** End code ***
   
   

2. Run the program. NOTE: The current date appears with two digits for year.

3. In the text box, enter a date with a year less than 60, such as 01/10/56. Note: As soon the "56" is entered, the year is displayed as "2056."

4. Enter a date with a year greater than 60, such as 12/01/99. NOTE: The date is shown with only the last two digits of the year omitting the century.

REFERENCES

For more information about SET CENTURY, search for CENTURY in the Visual FoxPro Help file.

Keywords          : FxprgGeneral vfoxwin kbprg
Version           : 5.0 5.0a
Platform          : WINDOWS
Issue type        : kbprb