Using VPLUS: An Introduction to Forms Design (32209-90004)

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the statement shown in Figure 6-5. Press ENTER to record this field

definition.

Figure 6-6. Field Menu for ORDNUM in the TOTALS Form

Action

Now, go to the Field Menu for ORDNUM in the TOTALS form. As you did with

the similar field in the ORDER form, change the field type to D, the data

type to DIG, and delete the initial value. Then, go to the Processing

Specifications area of the menu and add the statements shown in Figure

6-6. Press ENTER.

The first time the ORDER form is displayed by ENTRY, the value of SORDNUM

is its initial value 100001. Since no change is made to the SORDNUM save

field between execution of the first form (ORDER) and the second form

(TOTALS), both forms for a single order have the same order number,

initially 100001.

The next time the ORDER form is displayed, it is for a new order. As a

result of the calculations in the ORDNUM field of the form TOTALS, this

number is 1 greater than the previous order number; that is it is 100002.

This continues until the order number is incremented to its maximum val-

of 999999.

Note that the value of SORDNUM is tested before it is incremented. This

is done because the two ORDNUM fields and the SORDNUM save field are each

six digits long. A value greater than 999999 causes an overflow error

because it won't fit in these fields. To prevent such an error, the