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taLeftJustify

taLeftJustify = 0

Example​

function DefaultTextAlignment: TAlignment;
begin
  Result := taLeftJustify;
end;

Usage​

taLeftJustify selects left-aligned TAlignment rendering and Velox right-padding or trailing truncation for fixed-width fields.

Additional Technical Info​

taLeftJustify is the first member of Delphi's TAlignment enumeration. Standard consumers place the start of each text line at the left edge of the available area.

It is also the zero/default TField.Alignment value. Delphi object fields are zero-initialised, and the base TField constructor does not replace this value. Numeric field descendants deliberately change their default to taRightJustify.

Velox script exposure

Velox registers TAlignment as a hidden scripting type and exposes its members as constants. The current reduced TField import exposes DisplayText, DisplayWidth and other field members but omits Alignment; a script therefore cannot currently assign this constant to a dataset field through that documented surface. The constant can still be returned, compared or passed wherever a compatible TAlignment signature is available.

The example returns the enum value without changing product or dataset state. It is source-reviewed and is not executed by the documentation workflow.

Velox fixed-width behavior

When flat-file output is non-delimited, Velox obtains the field text first and then applies this branch:

  • if the text is shorter than DisplayWidth, it appends spaces until the configured width is reached; or
  • if the text is longer, it keeps the leftmost DisplayWidth units and silently removes trailing content.

For example, ABC at width 5 becomes ABC , while ABCDEFG at width 5 becomes ABCDE. No warning or overflow indicator is generated.

Trimming happens before width enforcement. If string quoting is enabled, the quotes are added before measurement and count toward the width; truncation can therefore remove data or a closing quote. Non-string fields use DisplayText, so display formatting also affects the measured content.

Delphi Length(string) and SetLength operate in UTF-16 code units on Windows, not encoded bytes or user-perceived characters. A configured width is therefore not automatically a byte width, and truncation can split a surrogate pair. Confirm the final file encoding and test non-ASCII boundary values when a partner specification defines byte positions.

Delimited output bypasses this entire branch. taCenter also bypasses it because Velox has no centred fixed-width case.

Side effects, errors and performance

The constant itself has no side effects. Native assignment to TField.Alignment can raise a dataset layout-change event when the dataset is active, but the current script TField wrapper does not expose that setter. Fixed-width padding/truncation allocates a string proportional to the configured width and can silently lose content; validate widths before production output.

External references

Created 2026-07-15