FORM SET LIST

Setting Contents of List Boxes and Combo Boxes

Introduction

In this module, we will explore how to set the contents of list boxes and combo boxes in forms. This is a fundamental skill for creating dynamic and interactive web forms. We will cover two methods: using an expression and using a set.

Method 1: Using an Expression

Command: FORM SET LIST formfield LIST expression

Parameters:

• formfield: The target list box or combo box in your form.
• expression: A character string or an expression that evaluates to a character string. Items in the expression must be separated by semicolons.

Example:

form set list fCDLFind.FieldName \
list " ProdCode ; ProdDesc ; UnitPrice ; QOH ; MinQty"

In this example, the combo box fCDLFind.FieldName is populated with field names specified in the string.

Method 2: Using a Set

Command: FORM SET LIST formfield FROM [ num ] [ setspec ] [FORMAT expression]

Parameters:

• formfield: The target list box or combo box in your form.
• num: The number of items to set in the list box or combo box. This can be an integer, a variable, or the word ALL.
• setspec: A set specification whose members are used to set the contents of the list box or combo box. If omitted, the current set is used.
• expression: An expression to format each item. This can be omitted if setspec is an unstructured application document.

Example:

form set list fCustomer.StateTab from states sorted by StCode \
format $ concat(StCode, " ", StDesc)

In this example, the list box fCustomer.StateTab is populated with state codes followed by state names, sorted by StCode.

Key Points to Remember

• When using an expression, ensure items are separated by semicolons.
• When using a set, you can specify the number of items and format each item using an expression.
• Data populated from a set is left-justified regardless of data type.

Practice Exercise

Try setting the contents of a list box in your form using both methods. Experiment with different expressions and sets to see how the contents change.