Administration and Programming Guide for OS/400

Net.Data Macro Variables

Net.Data lets you define and reference variables in a Net.Data macro. In addition, you can pass these variables from the macro to language environments and back. Net.Data tokens, such as variable names and values, and literal strings, can contain up to 256 KB of data. For OS/400, the maximum token size is determined by the operating system. Individual language environments can provide additional restrictions on the size of the values.

Net.Data variables can be defined depending on the type of variable and whether it has a predefined value. These variables can be categorized into the following types, based on how they are defined:

• Explicitly defined variables using the DEFINE statement in the DEFINE block
• Predefined variables, which are variables that are made available by Net.Data and are set to a value. This value usually cannot be changed.
• Implicitly defined variables, which are of four types:
  • Variables that are not explicitly defined but are instantiated when first assigned a value.
  • Parameter variables that are part of a FUNCTION block definition and that can only be referenced within a FUNCTION block.
  • Variables that are instantiated by Net.Data and correspond to form data or query string data.
  • Variables that are associated with a Net.Data table and that can only be referenced within a ROW block or REPORT block.

The following sections describe:

• Identifier Scope
• Defining Variables
• Referencing Variables
• Variable Types