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ConvertHtmlHexToTColor

function ConvertHtmlHexToTColor(Color: String): Integer;

Example​

procedure ScriptEvent(var Value: variant);
begin
  Value := ConvertHtmlHexToTColor('#336699'); // $00996633 in BGR order
end;

Usage​

ConvertHtmlHexToTColor converts a six-digit HTML RGB hex string to a Windows BGR TColor integer, returning red for other lengths.

Parameters

NameTypeDescription
ColorStringExpected as exactly six hexadecimal digits, optionally beginning with #. No trim is performed.

Returns

For six digits RRGGBB, the result is the integer $00BBGGRR. If the post-processing text length is not six, the function returns decimal 255, which is $000000FF and therefore red in TColor byte order.

The fallback is a valid colour, not an error indicator. A caller cannot distinguish an invalid-length input from the valid colour #FF0000 by inspecting the result alone.

Additional Technical Info​

ConvertHtmlHexToTColor converts six HTML-style RGB hexadecimal digits into the integer byte order used by a Windows TColor: $00BBGGRR.

It is a parser/converter only. It does not apply a colour to a component and it does not support CSS shorthand, alpha channels, colour names or surrounding whitespace. The example is fictional and source-reviewed only.

Implementation

  1. uPSI_vxCommon registers vxCommon.ConvertHtmlHexToTColor directly.
  2. The nested helper reads the first character. If it is #, StringReplace removes every hash character in the string, not only the leading one.
  3. A six-character result is reordered as '$00' + BB + GG + RR.
  4. Delphi StrToInt parses that $-prefixed hexadecimal text.
  5. Any other length returns 255.

Edge cases and quirks

  • Empty input attempts to read Color[1]. Product range checking is enabled, so it raises ERangeError before the length fallback.
  • A leading hash activates replacement of all hashes. For example, malformed '#12#3456' becomes '123456' and is accepted.
  • A hash that is not first is not removed and usually causes either the length fallback or a conversion error.
  • Six non-hex characters pass the length test and then raise EConvertError in StrToInt.
  • Eight-digit AARRGGBB/RRGGBBAA, three-digit CSS shorthand, colour names and whitespace-padded text return the red fallback because their lengths are not six.
  • Letter case is accepted by Delphi's hexadecimal parser.
  • The result is a raw Windows/VCL colour integer. It is not an HTML integer in RRGGBB order and has no alpha component.

Side effects and errors

The operation is pure. ERangeError and EConvertError propagate; the wrapper does not log or translate them. Validate/trim the input before calling when malformed text is possible.

Related entries

  • ExtractNumber is another permissive text-to-number helper, with different filtering and locale rules.

External references

Created 2026-07-15