angular - typescript checking using type guards -


i have method launches modalwindow takes element input (using $event.target) or number. trying perform check on type of input check treats element number if it's not. whether or not element number console.log outputted , else never runs.

launchmodal(element: number | any) {      if (<number>element) {        console.log('ele num', element);     } else {       const elementid = (event.target element).id;       const elementidarray = string(elementid).split('-');       this.currentrow = parseint(elementidarray[2], 10);      }     this.loadequipmentfullrowdatarequest(this.currentrow);    }

i following documentation advanced types @ official site

in typescript type system compile time only, in runtime code transpiled javascript , type information lost.

when if (<number>element) cast doesn't anything, allows write code refers element number (here aren't doing element it's meaningless).

in order check if value got number have use javascript methods:

if(typeof(element) === 'number')

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