What causes "Expected base64(id),base64(target),0|1 entries separated by '|'." in iOfficeAI/OfficeCLI?

Regenerate the encoded string from EncodeDumpDrawingHyperlinks rather than authoring by hand.

iOfficeAI/OfficeCLI · error · FormatException

Expected base64(id),base64(target),0|1 entries separated by

Error message

Expected base64(id),base64(target),0|1 entries separated by '|'.

What it means

Thrown by DecodeDumpDrawingHyperlinks when an entry in the pipe-delimited dump-replay string does not match the exact 'base64(id),base64(target),0|1' shape. This is a round-trip format produced by the sibling EncodeDumpDrawingHyperlinks for replaying dumped drawing hyperlinks without a JSON serializer in the single-file executable. FormatException (not ArgumentException) signals corrupt/malformed transport data rather than bad user input.

Source

Thrown at src/officecli/Handlers/Excel/ExcelHandler.Helpers.Drawing.cs:513

    {
        static string B64(string value) => Convert.ToBase64String(
            System.Text.Encoding.UTF8.GetBytes(value));
        return string.Join("|", hyperlinks.Select(h =>
            $"{B64(h.Id)},{B64(h.Target)},{(h.IsExternal ? "1" : "0")}"));
    }

    internal static List<DumpDrawingHyperlinkSpec> DecodeDumpDrawingHyperlinks(
        string encoded)
    {
        static string FromB64(string value) => System.Text.Encoding.UTF8.GetString(
            Convert.FromBase64String(value));
        var result = new List<DumpDrawingHyperlinkSpec>();
        if (string.IsNullOrEmpty(encoded)) return result;
        foreach (var entry in encoded.Split('|', StringSplitOptions.RemoveEmptyEntries))
        {
            var fields = entry.Split(',');
            if (fields.Length != 3 || (fields[2] != "0" && fields[2] != "1"))
                throw new FormatException(
                    "Expected base64(id),base64(target),0|1 entries separated by '|'.");
            result.Add(new DumpDrawingHyperlinkSpec
            {
                Id = FromB64(fields[0]),
                Target = FromB64(fields[1]),
                IsExternal = fields[2] == "1",
            });
        }
        return result;
    }

    /// <summary>
    /// Build the dump replay sequence for worksheet shapes without destroying
    /// real DrawingML groups. A grouped TwoCellAnchor is carried verbatim when
    /// every relationship referenced inside it is a hyperlink relationship;
    /// those lightweight relationships can be recreated safely on replay.
    ///
    /// Groups that reference package parts (pictures/charts/etc.) fall back to

View on GitHub (pinned to 1ced45e900)

Solutions

Regenerate the encoded string from EncodeDumpDrawingHyperlinks rather than authoring by hand.
If you must author, ensure every entry is exactly b64(id),b64(target),0 or b64(id),b64(target),1, joined by '|'.
Verify each id/target is standard base64 (A-Za-z0-9+/= only) so it cannot contain ',' or '|' and corrupt the split.
Check for shell quoting issues: wrap the whole value in single quotes so '|' and ',' are not interpreted.

Example fix

// before
DecodeDumpDrawingHyperlinks("id,target,1")
// after
DecodeDumpDrawingHyperlinks(Convert.ToBase64String(UTF8.GetBytes("id")) + "," + Convert.ToBase64String(UTF8.GetBytes("target")) + ",1")

Defensive patterns

Strategy: validation

Validate before calling

bool IsValidDumpHyperlinkEncoding(string encoded)
{
    if (string.IsNullOrEmpty(encoded)) return true;
    foreach (var entry in encoded.Split('|', StringSplitOptions.RemoveEmptyEntries))
    {
        var f = entry.Split(',');
        if (f.Length != 3 || (f[2] != "0" && f[2] != "1")) return false;
        try { Convert.FromBase64String(f[0]); Convert.FromBase64String(f[1]); }
        catch { return false; }
    }
    return true;
}

Type guard

static bool IsDumpHyperlinkEncoding(string s)
    => string.IsNullOrEmpty(s) || s.Split('|', StringSplitOptions.RemoveEmptyEntries)
        .All(e => { var f = e.Split(','); return f.Length == 3 && (f[2]=="0"||f[2]=="1"); });

Try / catch

try { var links = DecodeDumpDrawingHyperlinks(encoded); }
catch (FormatException ex) when (ex.Message.Contains("base64(id),base64(target)"))
{
    // the dump-replay stream is corrupt; regenerate via EncodeDumpDrawingHyperlinks
}

Prevention

Prefer regenerating the encoded string with EncodeDumpDrawingHyperlinks over hand-authoring.
Keep base64 payloads intact (do not strip '=' padding).
Shell-quote the whole value with single quotes so '|' and ',' survive.
Validate field count and flag char before decoding if the string crossed an untrusted boundary.

When it happens

Trigger: Decoding a string where an entry has !=3 comma-fields, or where the third field is not literally '0' or '1'. Examples: 'aGQ=bmV3.doc,2' (wrong flag), 'id,target,1' (forgot base64), 'aGQ=' (only one field), or a hand-edited pipe string that lost a field. Also triggers if a base64 payload itself was split or trimmed of its '=' padding so the comma split yields the wrong count.

Common situations: Hand-editing a dumped drawing-hyperlink replay string; passing the output through a shell/pipe that interpreted ',' or '|' specially; mixing versions where the encode format changed; truncating the string in a log/copy-paste so the last entry is partial.

Related errors

AI-assisted analysis of iOfficeAI/OfficeCLI@1ced45e900 (2026-08-13). Data as JSON: /api/errors/f0410958f469b998. Report an issue: GitHub.