2π
β
In the customTooltips function you can access the datasets by this._data.datasets. Then you can loop trough the datasets to see if borderdash exist. In the example below I used .map to create new array.
let data = this._data.datasets
let borderDash = data.map((item,index) => {
return {
label:item.label,
index,
borderDash: item.borderDash?true:false
}
})
console.log(borderDash)
Source:stackexchange.com