pb-modify

PowerBuilder Code Modification Workflow

MANDATORY: Follow these steps for EVERY PB code modification

Step 1: Understand Before Modifying

Before changing any PowerBuilder file:

1. Read the target object using pb_read_object to get the full source + parsed metadata
2. Check the inheritance chain using pb_get_inheritance — understand what this object inherits from and what inherits from it
3. Check dependencies using pb_get_dependencies — who uses this object? What will break?
4. Get a summary using pb_get_object_summary if you need a quick overview

NEVER modify a PB file without first understanding its inheritance and dependencies.

Step 2: Plan the Modification

Before writing code:

• Identify exactly which event/function/variable to modify
• Check if the modification affects inherited behavior (ancestors/descendants)
• If modifying an ancestor object: understand ALL descendants that will be impacted

Step 3: Apply the Modification

Use pb_modify_script for targeted find-and-replace:

• The tool creates automatic backups (.bak files)
• The tool verifies unique occurrence before replacing
• The tool invalidates the cache after modification

For new functions/events, insert at the correct location in the file:

• Instance variables go in type variables ... end variables section
• Functions go after the end type declaration
• Events go after functions

Step 4: Validate

After each modification:

1. Run pb_validate_syntax to check basic syntax
2. If validation passes, run pb_compile to do a full compile
3. Check compilation results — fix any errors immediately

Step 5: Compile and Deploy

The compilation process:

1. pb_compile executes PBAutoBuild250 and returns structured results
2. If successful, PBDs are automatically copied to the exe directory
3. Check for warnings — they may indicate issues

PowerScript Conventions

Variable naming

• is_ = instance string (e.g., is_customer_name)
• il_ = instance long (e.g., il_customer_id)
• ib_ = instance boolean (e.g., ib_dirty)
• id_ = instance decimal/date
• ii_ = instance integer
• ls_ = local string, ll_ = local long, etc.

Function naming

• of_ = object function (public method)
• wf_ = window function (private to this window)
• gf_ = global function

Event naming

• ue_ prefix = user-defined events (custom)
• Standard events: open, close, clicked, constructor, destructor

Object naming

• w_ = window
• nvo_ = non-visual object
• uo_ = user object (visual)
• d_ = datawindow
• m_ = menu
• st_ = static text, sle_ = single line edit, mle_ = multi-line edit
• cb_ = command button, dw_ = datawindow control
• ddlb_ = dropdown list box, rb_ = radio button, cbx_ = checkbox

File structure (.sr* files)

$PBExportHeader$objectname.srw
forward                          <- DO NOT MODIFY unless you understand it
global type ... from ...
end type
end forward

shared variables                 <- shared across instances
end variables

type variables                   <- instance variables
end variables

forward prototypes               <- function declarations
end prototypes

type prototypes                  <- more declarations
end prototypes

event open;...end event          <- events
public function ...end function  <- functions

on objectname.create             <- lifecycle - DO NOT MODIFY
on objectname.destroy            <- lifecycle - DO NOT MODIFY

NEVER modify forward, on create, or on destroy sections unless you fully understand the impact. These are generated by the PB IDE.

Common patterns

• SQLCA = default transaction object (database connection)
• this. = reference to current object
• parent. = reference to parent window
• messagebox() = show message dialog
• destroy = free memory for dynamically created objects
• create = instantiate objects
• trigger event = fire an event
• post event = queue an event for later processing

Error Recovery

If compilation fails:

1. Read the error messages carefully
2. The .bak backup file exists — you can restore if needed
3. Fix the issue and recompile
4. Never leave the codebase in a broken state