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what is the best usage for the “typeof” JavaScript function?
if (typeof (myvar) == 'undefined') {
//or
if (typeof (myvar) == undefined) {
//or
if (typeof myvar == 'undefined') {
//or
if (typeof myvar == undefined) {
Thanks
typeofis an operator, not a function, and returns a string; so do not use parentheses and do compare it to a string.When you compare things, avoid type coercion unless you need it (i.e. use
===not==).