By (PointAnimation)
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Gets or sets the total amount by which the animation changes its starting value.
<object By="Point" .../>
value = object.By
object.By = value
Property Value
Type: Point
The total amount by which the animation changes its starting value.
This property is read/write. The default value is null.
Remarks
Point parallels a convention that is supported by a type converter, such that properties that take a Point as their value can specify a Point as a formatted string. The type converter generates a new Point value based on processing the string. The type converter functions both for XAML and script usages. In both cases, you supply a quoted string. The format of that string is an X,Y value pair. Alternatively, you can use a space instead of a comma as the delimiter between X and Y in the string.
For more information about scripting usages, see the "Remarks" section in the Point reference topic. The properties of PointAnimation represent a case where the object model provides access to an actual Point as a return value if you get this property at run time. This means that you can potentially use the X and Y properties of the returned Point to adjust the animation either before or while it runs.
Use the By property when you want to animate a value by a certain amount instead of specifying a starting or ending value. You may also use the By property with the From property. The following table summarizes how the From, To, and By properties may be used together or separately to determine an animation's target values.
Properties specified |
Resulting behavior |
|---|---|
From |
The animation progresses from the value specified by the From property to the base value of the property that is being animated. |
From and To |
The animation progresses from the value specified by the From property to the value specified by the To property. |
From and By |
The animation progresses from the value specified by the From property to the value specified by the sum of the From and By properties. |
To |
The animation progresses from the animated property's base value or a previous animation's output value to the value specified by the To property. |
By |
The animation progresses from the base value of the property that is being animated or a previous animation's output value to the sum of that value and the value specified by the By property. |
.gif "Note") Note: |
|---|
If you set both the To and By properties, the To property takes precedence and the By property is ignored. |
To use other interpolation methods or to animate between more than two target values, use a PointAnimationUsingKeyFrames object.