Form field input differences

This topic describes differences in field input between I4GL and Genero BDL.

PICTURE chars disappear with null field

With IBM® Informix® 4GL, the mask characters defined in the PICTURE attribute of the field are still displayed when you leave the field with no value.

With Genero BDL, the form field is left completly empty, without any character from the PICTURE input mask. When re-entering the form field with the PICTURE attribute, the mask characters appear again.

For example:

DATABASE FORMONLY
SCREEN
{          
[f01      ]
[f02      ]
}   
END 
ATTRIBUTES
f01 = FORMONLY.field1, PICTURE="AA-###-AA";
f02 = FORMONLY.field2;
END

MAIN
    DEFINE rec RECORD
           field1 CHAR(9),
           field2 CHAR(9)
       END RECORD
    OPEN FORM f1 FROM "form"
    DISPLAY FORM f1
    INPUT BY NAME rec.*
    DISPLAY "rec.field1 = ", rec.field1
END MAIN

Genero BDL implements a consistent behavior while I4GL does not: The mask characters of a field with a PICTURE attribute are part of the value. If a field is NULL, no mask characters must be shown to the user to have a visual result that corresponds to the actual field value.

Space clears whole DATETIME and INTERVAL field

With IBM Informix 4GL, if a DATETIME or INTERVAL field contains a value, a single space input at the beginning of the field does not erase the whole value.

With Genero BDL, a single space input at the beginning of the field erases the current DATETIME or INTERVAL value, as done for numeric and DATE types.

For example:

DATABASE FORMONLY
SCREEN
{          
[f01                        ]
[f02                        ]
[f03                        ]
[f04                        ]
}   
END 
ATTRIBUTES
f01 = FORMONLY.field1;
f02 = FORMONLY.field2;
f03 = FORMONLY.field3;
f04 = FORMONLY.field4;
END

MAIN
    DEFINE rec RECORD
           field1 INTEGER,
           field2 DATE,
           field3 DATETIME YEAR TO SECOND,
           field4 INTERVAL HOUR(6) TO MINUTE
       END RECORD
    OPEN FORM f1 FROM "form"
    DISPLAY FORM f1
    LET rec.field1 = 9999
    LET rec.field2 = MDY(12,24,2002)
    LET rec.field3 = "2012-11-24 11:22:33"
    LET rec.field4 = "-9999:55"
    INPUT BY NAME rec.* WITHOUT DEFAULTS
END MAIN

The input behavior of Genero BDL for DATETIME and INTERVAL fields is consistent with numeric and DATE types: Entering a space must erase all the value.

get_fldbuf() returns NULL for empty fields

With IBM Informix 4GL, after clearing the form field with CLEAR FORM or CLEAR field-name, the get_fldbuf() function returns a set of space characters for a CHAR field. For other types INTEGER or DATE, I4GL returns NULL when the field is empty.

In such case, with Genero BDL, get_fldbuf() returns NULL when the field is empty.

The Genero BDL behavior is more consistent than I4GL: Returned NULL reflects the empty field seen by the end user.

get_flgbuf() returns stars when overflow

With IBM Informix 4GL, when a numeric field is to show to hold the value, your can see *** stars to indicate an overflow, but the get_fldbuf() function returns the actual value of the program variable.

The Genero BDL behavior is more consistent than I4GL: In such case, get_fldbuf() returns *** stars as seen by the user.

Review the form definition by increasing the width of the form field, or use values that fit into the field size.