Copy Text Safely into Code Fields

Copy Text Safely into Code Fields

An import routine receives item identifiers from an external system as free text. Your teammate wired it straight into a Code[20] — and the import now dies with "The length of the string is 27, but it must be less than or equal to 20 characters." This is one of AL's classic runtime errors: assigning oversized Text to a Code field doesn't truncate; it crashes.

The starter code reproduces that bug. Fix it.

Requirements

Create a codeunit named "Code Normalizer" with a public procedure:

procedure ToCode20(Input: Text): Code[20]

Rules:

1. Remove leading and trailing whitespace first.
2. Then truncate to at most 20 characters — the procedure must never raise a string-overflow error, no matter how long the input is.
3. The result is uppercase, as every Code value is. (The Text → Code conversion does this for you on return/assignment — you don't need UpperCase unless you want it explicit.)
4. Empty or whitespace-only input returns an empty code.

What the tests check

The grading tests call ToCode20 with a short lowercase value (expected back uppercased and otherwise unchanged), a 40-character value (the first 20 characters are expected, not an error), a padded value (whitespace must be trimmed before truncating), an empty string, a whitespace-only value, and a value wrapped in tabs. Whitespace means more than spaces: Text.Trim() handles tabs, while the old DelChr(..., '<>', ' ') idiom strips only spaces and fails the tab cases.

Learn More

• Code data type
• Text data type
• Text.Trim method
• Text.CopyStr method
• Text.MaxStrLen method