how to change timestamp js code example

Example 1: convert date to timestamp javascript

//  human date --> timestamp

function toTimestamp(strDate){
   var datum = Date.parse(strDate);
   return datum/1000;
}
alert(toTimestamp('02/13/2009 23:31:30'));

Example 2: convert date to timestamp javascript

const toTimestamp=(strDate)=>{
   var datum = Date.parse(strDate);
   return datum/1000;
}
console.log(toTimestamp('02/13/2009 23:31:30'));