Base64EncodeBytes

Function Base64EncodeBytes( Value : TBytes) : string

Example

procedure ScriptEvent(var Value: variant);
var
  Bytes: TBytes;
begin
  SetLength(Bytes, 3);
  Bytes[0] := 1;
  Bytes[1] := 2;
  Bytes[2] := 3;
  Value := Base64EncodeBytes(Bytes);  // AQID
end;

Usage

Base64EncodeBytes encodes an exact byte array as unwrapped standard Base64 text.

Parameters

Name	Type	Description
Value	TBytes	Bytes to encode. The declaration passes the dynamic-array reference by value; the helper does not modify its elements.

Returns

Unwrapped standard Base64 text with = padding when required. A zero-length array returns an empty string.

Behaviour

• Every source byte, including zero bytes, participates in the encoded value.
• Output uses the standard + and / alphabet and conventional = padding.
• No text encoding, Unicode normalisation or line wrapping occurs.
• The source array remains unchanged.

Important usage notes

• This is not URL-safe Base64 and does not remove padding.
• A dynamic array is reference-counted. Although the function declaration is by value, Velox only reads it; the caller should still avoid mutating the same array concurrently.
• Base64 is reversible and does not detect modification. Add a suitable MAC or signature when integrity or authenticity is required.

Usage notes

Use this function for binary values already held in memory. Use Base64EncodeFile for a file path, while noting that the file helper also reads the whole file into memory.

Additional Technical Info

Base64EncodeBytes converts the exact contents of a TBytes array to standard Base64 text. It performs no character-set conversion and inserts no line breaks.

The example is source-reviewed and was not executed by the documentation workflow.

Implementation

Velox creates TBase64Encoding with line length 0, calls Delphi's EncodeBytesToString, and frees the encoder in a finally block.

Side effects

None beyond temporary allocation.

Errors

Memory-allocation and underlying Delphi exceptions propagate to the script.

Performance and concurrency

The entire output is built in memory and is approximately four characters for every three input bytes, plus padding. Each call owns a separate encoder; independent arrays can be encoded concurrently.

Related entries

• Base64DecodeBytes performs the reverse operation.
• Base64Encode first converts a string to UTF-8.
• HMACSHA256 uses this helper to format its 32-byte MAC.

External references

• Embarcadero DocWiki: TNetEncoding.EncodeBytesToString - the exact Delphi operation called by the wrapper.
• Free Pascal: EncodeStringBase64 - related Free Pascal Base64 encoding documentation.

Created 2026-07-15