javascript - "Cannot read property .. of null" after checking for undefined object -


i have object need check if defined. also, want check if property of object true or false.

so want is

if ((typeof myvar !== 'undefined') && (myvar.ismale === false)) {      // 1  }  else{       // 2  }

but logic gives me error

uncaught typeerror: cannot read property 'ismale' of null

what best login handle condition ?

thanks !

you need test further, either exclusion:

if (typeof myvar != 'undefined' && myvar && myvar.ismale === false) {

or inclusion:

if (typeof myvar == 'object' && mvar && myvar.ismale === false) {

but there objects return values other "object" typeof tests (e.g. host objects may , function objects do).

or explicit conversion:

if (typeof myvar != 'undefined' && object(myvar).ismale === false) {

edit

the additional && myvar test catch nan , null pass typeof test.


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