Expressions: Type 1
In the Expression box in the Invoice validation group box you type an expression to validate a numerical field.
There are two types of expressions. Type 1 validates the current field in relation to other fields.
Type 1 can be:
- A mathematical expression. Refers to the current field but does not name it.
- A relational operator followed by a field name or arithmetic expression. Refers to the current field but does not name it.
Examples (assuming the current field is FieldA):
<=FieldB | FieldA must be less than or equal to FieldB |
>FieldC | FieldA must be greater than FieldC |
= FieldD + FieldE | FieldA must be equal to the sum of FieldD and FieldE |
If you omit the relational operator, the program assumes "=" by default.
Example (assuming the current field is FieldA):
FieldB+FieldC | (The same as =FieldB+FieldC) |
Type 1 expressions can always be rewritten as type 2 expressions. For example, these two expressions mean the same thing (assuming the current field is FieldA):
Type 1: =FieldB+FieldC
Type 2: FieldA=FieldB+FieldC