dotnet/wpf · error · ArgumentException

SR.Timing_InvalidArgFinitePositive

Error message

SR.Timing_InvalidArgFinitePositive

What it means

Timeline.SpeedRatio is validated by ValidateSpeedRatio, which requires a finite positive double: > 0, <= double.MaxValue, and not NaN. Zero, negative, NaN, or +Infinity values throw ArgumentException with Timing_InvalidArgFinitePositive.

Solutions

  1. Validate/guard before assignment: double.IsFinite(v) && v > 0 (note Infinity must be excluded).
  2. Clamp small/invalid values to a minimum like 0.001 or fall back to 1.
  3. For dynamic speed control, coerce the bound value in a value converter or property setter.

Example fix

// before
timeline.SpeedRatio = newSpeed; // may be 0 or NaN
// after
timeline.SpeedRatio = double.IsFinite(newSpeed) && newSpeed > 0 ? newSpeed : 1.0;
Defensive patterns

Strategy: validation

Validate before calling

double v = double.IsFinite(speed) && speed > 0 ? speed : 1.0;
timeline.SpeedRatio = v;

Type guard

static bool IsValidSpeedRatio(double v) => double.IsFinite(v) && v > 0;
static double SafeSpeedRatio(double v) => double.IsFinite(v) && v > 0 ? v : 1.0;

Try / catch

try { timeline.SpeedRatio = speed; }
catch (ArgumentException) { timeline.SpeedRatio = 1.0; }

Prevention

When it happens

Trigger: timeline.SpeedRatio = 0, = -2, = double.NaN, or = double.PositiveInfinity (Infinity exceeds double.MaxValue per this check). Also via data binding to a value that can be 0.

Common situations: Computing speed from a divisor that yields 0 or Infinity (speed = distance/time with time 0); NaN from double.TryParse of empty input; UI numeric fields allowing 0 or negatives.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

AI-assisted analysis of dotnet/wpf@81131a70a4 (2026-09-14). Data as JSON: /api/errors/9a9442d921f5fbd3. Report an issue: GitHub.

Appendix: source

Thrown at src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/Media/Animation/Timeline.cs:601

        public double SpeedRatio
        {
            get
            {
                return (double)GetValue(SpeedRatioProperty);
            }
            set
            {
                SetValue(SpeedRatioProperty, value);
            }
        }

        private static bool ValidateSpeedRatio(object value)
        {
            double newValue = (double)value;

            if (newValue <= 0 || newValue > double.MaxValue || double.IsNaN(newValue))
            {
                throw new ArgumentException(SR.Timing_InvalidArgFinitePositive, nameof(value));
            }

            return true;
        }

        #endregion // SpeedRatio Property

        #endregion // Properties

        #region Methods

        /// <summary>
        /// Called by the <see ref="Clock.FromTimeline" /> method to
        /// create a type-specific clock for this Timeline.
        /// </summary>
        /// <returns>
        /// A clock for this Timeline.
        /// </returns>

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