Function toDashLengths

toDashLengths(
dash: readonly number[] | IStroke.DashStyle | null | undefined,
): number[] | null
A dash as alternating dash and space lengths in line widths, or null for a solid line.
Parameters
- dash: readonly number[] | IStroke.DashStyle | null | undefined
  A preset, or a custom pattern as Properties.dash holds it (percentages of the width).
Returns number[] | null
Example
```
IStroke.toDashLengths(IStroke.DashStyle.SysDot); // [1, 1]
IStroke.toDashLengths([400, 300]); // [4, 3]
```