iOfficeAI/OfficeCLI · error · ArgumentException

Invalid '{propertyName}' value '{value}'. Expected a finite

Error message

Invalid '{propertyName}' value '{value}'. Expected a finite number.

What it means

Thrown by ParseHelpers.SafeParseDouble when the value is not a finite number. Parsing uses NumberStyles.Float (NOT the default Float|AllowThousands), so it deliberately rejects thousands separators — this prevents a comma-decimal-locale input like '45,5' silently becoming 455. NaN and +/-Infinity are also rejected even if they parse.

Source

Thrown at src/officecli/Core/ParseHelpers.cs:489

        // inherently position-ordered, and lets a future text-mutating path process
        // ranges back-to-front (descending) so earlier offsets stay valid — the same
        // reason ProcessFindInParagraph iterates its matches in reverse.
        result.Sort((a, b) => a.Start != b.Start ? a.Start.CompareTo(b.Start) : a.End.CompareTo(b.End));
        return result;
    }

    /// <summary>
    /// Safely parse a string as double, throwing ArgumentException with a clear message on failure.
    /// </summary>
    public static double SafeParseDouble(string value, string propertyName)
    {
        // NumberStyles.Float (NOT the default Float|AllowThousands) — matches every
        // other numeric parser in this file. AllowThousands would silently strip a
        // decimal comma ("45,5" -> 455), producing a 10x/1000x-wrong value from a
        // comma-decimal-locale input instead of rejecting it.
        if (!double.TryParse(value, NumberStyles.Float, CultureInfo.InvariantCulture, out var result)
            || double.IsNaN(result) || double.IsInfinity(result))
            throw new ArgumentException($"Invalid '{propertyName}' value '{value}'. Expected a finite number.");
        return result;
    }

    /// <summary>
    /// Parse a rotation value in degrees. Rejects non-finite, NaN, and values
    /// outside [-3600, 3600] degrees (ten full revolutions either direction).
    /// OOXML stores rotation as ST_Angle (60000ths of a degree) which fits in
    /// an Int32 up to ~±35790°, but values above ~±3600° are functionally
    /// indistinguishable from their modulo-360 reduction while opening the
    /// door to silent overflow on the (deg * 60000) multiply. The clamp is
    /// applied uniformly across pptx shape/group/connector add+set sites.
    /// </summary>
    public static double SafeParseRotationDegrees(string value, string propertyName)
    {
        var deg = SafeParseDouble(value, propertyName);
        if (deg < -3600 || deg > 3600)
            throw new ArgumentException($"Invalid '{propertyName}' value '{value}': degrees must be in [-3600, 3600].");
        return deg;

View on GitHub (pinned to 1ced45e900)

Solutions

  1. Use a plain invariant-culture number, e.g. '45.5' with a dot decimal and no thousands separators.
  2. Strip any unit suffix ('%', 'pt', 'cm', 'in') only if the specific caller documents it strips them — otherwise pass the bare number.
  3. For locale-comma decimals, convert to a dot decimal before submitting.

Example fix

// before
charspacing="45,5"
// after
charspacing="45.5"
Defensive patterns

Strategy: validation

Validate before calling

// Pre-validate with the SAME NumberStyles.Float rule the parser uses:
static bool IsFiniteNumber(string value)
    => double.TryParse(value, System.Globalization.NumberStyles.Float,
           System.Globalization.CultureInfo.InvariantCulture, out var d)
       && !double.IsNaN(d) && !double.IsInfinity(d);

Prevention

When it happens

Trigger: Any numeric property routed through SafeParseDouble: rotation (non-PPT), charspacing, crop, width, twips, trendline.forward/backward/intercept, axis min/max/unit, logBase, alpha, etc. Triggered by non-numeric text, a locale-comma decimal ('45,5'), thousands grouping ('1,000'), 'NaN', 'Infinity', or trailing units left on the value.

Common situations: Passing '45,5' in a comma-decimal locale (must be '45.5'); passing '100%' with the '%' still attached when the caller did not strip it; empty string for a numeric field; copy-pasting '1.024,5' (EU format) from a spreadsheet.

Related errors

AI-assisted analysis of iOfficeAI/OfficeCLI@1ced45e900 (2026-08-13). Data as JSON: /api/errors/aabf1567bd652e3c. Report an issue: GitHub.