Javascript == operator between single value and array -


can please explain why below statements alert 'check passed' in javascript? code comparing string object against array, , expecting fail.

var somearray = ['current'];  if('current' == somearray){    alert('check passed'); }else{    alert('check failed'); }

it alerts 'check passed'.

when comparing == javascript tries coerce left , right values same types. in case tries coerce them both strings.

when arrays coerced strings(its tostring function called) each element of array joined together. in case ["current"] becomes "current" so: 

"current" == somearray //becomes "current" == "current"

with multiple elements

["current","values"] become "current,values"

if not want happen use value , type compare operator ===

if("current" === somearray){    alert('check passed'); }else{    alert('check failed'); }

demo

var somearray = ["current"];    if("current" === somearray){     alert('check passed');  }else{     alert('check failed');  }


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