Field_Value_Table - DataDictionary

Parameter	Description
iField	Number of the column in the table

 Property Integer Field_Value_Table

Write Access:

Set Field_Value_Table iField to IntegerVariable/Value

If a column needs to be validated against one of two values, a limited set of values, or a range of values, you can use the checkbox (see Field_CheckBox_Values), range (see Field_Value_Range) or check (see Field_Value_Check) validations.

In many cases, you will find that these types of validations are too limited for your needs. In such a case, you may use column validation tables.

Sample

Set Field_Value_Table Field Customer.Status to oStatusTable

Using a validation table has the following advantages:

• You can specify a larger number of valid values than can easily fit within a check string
• You can specify and display a description for each value
• You can dynamically maintain your list of values (i.e., the values do not have to be coded directly in your program)
• You can make the list choices optional (i.e., you can display a list of suggested values during data entry but users are not required to make a selection from the list)

When a validation error occurs, the error number and text specified for the column in the Field_Error property are used to report an error. If no text was defined, a standard check-error text will be reported.

The use of validation tables provides tremendous flexibility. They will be discussed in greater detail in Using Validation Tables. For now, we will introduce the primary validation-table classes:

ValidationTable

This class allows you to maintain a list of valid values.

Object oStatusTable is a ValidationTable

     Procedure Fill_List
          Send Add_Table_Value "O"
          Send Add_Table_Value "C"
          Send Add_Table_Value "D"
     End_Procedure

End_Object

DescriptionValidationTable

This class allows you to maintain a list of valid values and their associated descriptions.

Object oStatusTable is a DescriptionValidationTable
     Set Table_Title to "Customer Status"

     Procedure Fill_List
          Send Add_Table_Value "O"  "Opened"
          Send Add_Table_Value "C"  "Closed"
          Send Add_Table_Value "D"  "Flagged for Deletion"
     End_Procedure

End_Object

FileValidationTable

This class allows you to maintain a list of values and descriptions that can be easily loaded from a specified DataFlex table.

Object Status_Table is a FileValidationTable
    Set Main_File to CustStat.File_Number
End_Object

CodeValidationTable

This class allows you to load your data and description values from the DataFlex Code List.

Object oStatusTable is a CodeValidationTable
    Set Type_Value to "Status"
End_Object

Any of the above validation tables can be linked to a column with the Field_Value_Table message in a data dictionary.

Set Field_Value_Table Field Customer.Status to oStatusTable

Defining Data Dictionary Field Attributes | Using Validation Tables