javascript - Best way to add null checker to querySelector in jquery -


i have parsed xml , i'm using queryselector

for example:

this.queryselector("type").textcontent

sometimes value of this.queryselector("type") null previous line returns error.

what beautiful way avoid errors?

i'm doing following:

example = this.queryselector("type") != null ? this.queryselector("type").textcontent : "" //ugly!

but long , looks bad.

other way: own function findinxml(this, "type"), when want deeper it's looks that:

findinxml(findinxml(this, "type"), "sth") // ugly!

i prefer use way example:

this.findxml("type").findxml("sth") //looks nice

one call queryselector:

var typeel; var example = (typeel = this.queryselector("type")) ? typeel.textcontent : '';

jsperf agrees:

https://jsperf.com/nullqueryselector/1


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