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StrToDate

function StrToDate(const S: string): TDateTime;

Example​

procedure ScriptEvent(var Value: variant);
begin
  // This input assumes the Velox host uses a day/month/year short-date format.
  Value := StrToDate('16/07/2026');
end;

Usage​

StrToDate parses a date string with the Velox process's global host format settings and raises when parsing fails.

Parameters

NameTypeDescription
Sstring, constDate text expected to match the host process's short-date format, separators, names and year rules.

Returns

A TDateTime containing the parsed Gregorian date with a zero time portion.

Behaviour

  • Numeric field order follows FormatSettings.ShortDateFormat; a portable script cannot assume day/month/year or month/day/year.
  • Named months/day names are compared against the format settings when the active pattern requests them.
  • A missing year is replaced with the host's current year. A missing day becomes day one where the active format permits omission. A month is required.
  • A short year is expanded using TwoDigitYearCenturyWindow.
  • Leading or embedded blanks accepted around configured separators depend on the active date format; trailing unconsumed text fails.
  • The result is date-only at midnight and carries no timezone.

Errors

Invalid syntax, invalid field combinations or unmatched locale text raise EConvertError. The exception includes locale/runtime text and the supplied value; do not parse the message as an interface. Velox does not catch it.

Usage notes

For integration data, avoid relying on a server's interactive regional settings. Use a deliberately specified Velox date format/conversion path when the source format is contractually fixed.

Additional Technical Info​

StrToDate parses a date-only string using the Velox process's current global date-format settings. It returns the encoded date at midnight or raises when the entire string cannot be parsed.

The example is fictional, source-reviewed and intentionally locale-dependent. It was not executed by the documentation workflow.

Implementation

The modified PascalScript date library declares StrToDate and runtime-registers System.SysUtils.StrToDate(S) directly. The installed Delphi 37.0 overload passes the process-global FormatSettings record to TryStrToDate. Its scanner parses ShortDateFormat, DateSeparator, locale month/day names and era rules, requires the parser to consume the full string, and then calls TryEncodeDate. Failure is converted to EConvertError.

Edge cases and quirks

  • The same text can mean different dates or fail on different Velox hosts because the one-argument overload always uses global process settings.
  • Omitting a year introduces a current-clock dependency, so the same input can produce a different year later.
  • Concurrent mutation of global FormatSettings can race with parsing. Prefer an unambiguous governed input format and a matching Velox conversion helper where available.
  • The input is not treated as ISO 8601 merely because it resembles one; the active short-date pattern remains authoritative.
  • Free Pascal offers the same one-argument and format-settings concepts, but parser details and accepted text can differ. Installed Delphi defines Velox behaviour.

Side effects

No persistent state is changed. The routine reads global format settings and, when needed, the current year.

Performance and concurrency

Linear in the short input/pattern length, with small fixed locale-name scans and no external I/O. Reads of mutable global settings make concurrent locale reconfiguration unsafe.

Related entries

  • DateToStr formats a date with host settings.
  • vxStrToDate is the Velox conversion helper when its governed format rules are required.

External references

Created 2026-07-15